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- ==================================
- Built-in template tags and filters
- ==================================
- This document describes Django's built-in template tags and filters. It is
- recommended that you use the :doc:`automatic documentation
- </ref/contrib/admin/admindocs>`, if available, as this will also include
- documentation for any custom tags or filters installed.
- .. _ref-templates-builtins-tags:
- Built-in tag reference
- ======================
- .. templatetag:: autoescape
- ``autoescape``
- --------------
- Controls the current auto-escaping behavior. This tag takes either ``on`` or
- ``off`` as an argument and that determines whether auto-escaping is in effect
- inside the block. The block is closed with an ``endautoescape`` ending tag.
- Sample usage:
- .. code-block:: html+django
- {% autoescape on %}
- {{ body }}
- {% endautoescape %}
- When auto-escaping is in effect, all content derived from variables has HTML
- escaping applied before placing the result into the output (but after any
- filters are applied). This is equivalent to manually applying the
- :tfilter:`escape` filter to each variable.
- The only exceptions are variables already marked as "safe" from escaping.
- Variables could be marked as "safe" by the code which populated the variable,
- by applying the :tfilter:`safe` or :tfilter:`escape` filters, or because it's
- the result of a previous filter that marked the string as "safe".
- Within the scope of disabled auto-escaping, chaining filters, including
- :tfilter:`escape`, may cause unexpected (but documented) results such as the
- following:
- .. code-block:: html+django
- {% autoescape off %}
- {{ my_list|join:", "|escape }}
- {% endautoescape %}
- The above code will output the joined elements of ``my_list`` unescaped. This
- is because the filter chaining sequence executes first :tfilter:`join` on
- ``my_list`` (without applying escaping to each item since ``autoescape`` is
- ``off``), marking the result as safe. Subsequently, this safe result will be
- fed to :tfilter:`escape` filter, which does not apply a second round of
- escaping.
- In order to properly escape every element in a sequence, use the
- :tfilter:`escapeseq` filter:
- .. code-block:: html+django
- {% autoescape off %}
- {{ my_list|escapeseq|join:", " }}
- {% endautoescape %}
- .. templatetag:: block
- ``block``
- ---------
- Defines a block that can be overridden by child templates. See
- :ref:`Template inheritance <template-inheritance>` for more information.
- .. templatetag:: comment
- ``comment``
- -----------
- Ignores everything between ``{% comment %}`` and ``{% endcomment %}``.
- An optional note may be inserted in the first tag. For example, this is
- useful when commenting out code for documenting why the code was disabled.
- Sample usage:
- .. code-block:: html+django
- <p>Rendered text with {{ pub_date|date:"c" }}</p>
- {% comment "Optional note" %}
- <p>Commented out text with {{ create_date|date:"c" }}</p>
- {% endcomment %}
- ``comment`` tags cannot be nested.
- .. templatetag:: csrf_token
- ``csrf_token``
- --------------
- This tag is used for CSRF protection, as described in the documentation for
- :doc:`Cross Site Request Forgeries </ref/csrf>`.
- .. templatetag:: cycle
- ``cycle``
- ---------
- Produces one of its arguments each time this tag is encountered. The first
- argument is produced on the first encounter, the second argument on the second
- encounter, and so forth. Once all arguments are exhausted, the tag cycles to
- the first argument and produces it again.
- This tag is particularly useful in a loop:
- .. code-block:: html+django
- {% for o in some_list %}
- <tr class="{% cycle 'row1' 'row2' %}">
- ...
- </tr>
- {% endfor %}
- The first iteration produces HTML that refers to class ``row1``, the second to
- ``row2``, the third to ``row1`` again, and so on for each iteration of the
- loop.
- You can use variables, too. For example, if you have two template variables,
- ``rowvalue1`` and ``rowvalue2``, you can alternate between their values like
- this:
- .. code-block:: html+django
- {% for o in some_list %}
- <tr class="{% cycle rowvalue1 rowvalue2 %}">
- ...
- </tr>
- {% endfor %}
- Variables included in the cycle will be escaped. You can disable auto-escaping
- with:
- .. code-block:: html+django
- {% for o in some_list %}
- <tr class="{% autoescape off %}{% cycle rowvalue1 rowvalue2 %}{% endautoescape %}">
- ...
- </tr>
- {% endfor %}
- You can mix variables and strings:
- .. code-block:: html+django
- {% for o in some_list %}
- <tr class="{% cycle 'row1' rowvalue2 'row3' %}">
- ...
- </tr>
- {% endfor %}
- In some cases you might want to refer to the current value of a cycle
- without advancing to the next value. To do this,
- give the ``{% cycle %}`` tag a name, using "as", like this:
- .. code-block:: html+django
- {% cycle 'row1' 'row2' as rowcolors %}
- From then on, you can insert the current value of the cycle wherever you'd like
- in your template by referencing the cycle name as a context variable. If you
- want to move the cycle to the next value independently of the original
- ``cycle`` tag, you can use another ``cycle`` tag and specify the name of the
- variable. So, the following template:
- .. code-block:: html+django
- <tr>
- <td class="{% cycle 'row1' 'row2' as rowcolors %}">...</td>
- <td class="{{ rowcolors }}">...</td>
- </tr>
- <tr>
- <td class="{% cycle rowcolors %}">...</td>
- <td class="{{ rowcolors }}">...</td>
- </tr>
- would output:
- .. code-block:: html+django
- <tr>
- <td class="row1">...</td>
- <td class="row1">...</td>
- </tr>
- <tr>
- <td class="row2">...</td>
- <td class="row2">...</td>
- </tr>
- You can use any number of values in a ``cycle`` tag, separated by spaces.
- Values enclosed in single quotes (``'``) or double quotes (``"``) are treated
- as string literals, while values without quotes are treated as template
- variables.
- By default, when you use the ``as`` keyword with the cycle tag, the
- usage of ``{% cycle %}`` that initiates the cycle will itself produce
- the first value in the cycle. This could be a problem if you want to
- use the value in a nested loop or an included template. If you only want
- to declare the cycle but not produce the first value, you can add a
- ``silent`` keyword as the last keyword in the tag. For example:
- .. code-block:: html+django
- {% for obj in some_list %}
- {% cycle 'row1' 'row2' as rowcolors silent %}
- <tr class="{{ rowcolors }}">{% include "subtemplate.html" %}</tr>
- {% endfor %}
- This will output a list of ``<tr>`` elements with ``class``
- alternating between ``row1`` and ``row2``. The subtemplate will have
- access to ``rowcolors`` in its context and the value will match the class
- of the ``<tr>`` that encloses it. If the ``silent`` keyword were to be
- omitted, ``row1`` and ``row2`` would be emitted as normal text, outside the
- ``<tr>`` element.
- When the silent keyword is used on a cycle definition, the silence
- automatically applies to all subsequent uses of that specific cycle tag.
- The following template would output *nothing*, even though the second
- call to ``{% cycle %}`` doesn't specify ``silent``:
- .. code-block:: html+django
- {% cycle 'row1' 'row2' as rowcolors silent %}
- {% cycle rowcolors %}
- You can use the :ttag:`resetcycle` tag to make a ``{% cycle %}`` tag restart
- from its first value when it's next encountered.
- .. templatetag:: debug
- ``debug``
- ---------
- Outputs a whole load of debugging information, including the current context
- and imported modules. ``{% debug %}`` outputs nothing when the :setting:`DEBUG`
- setting is ``False``.
- .. templatetag:: extends
- ``extends``
- -----------
- Signals that this template extends a parent template.
- This tag can be used in two ways:
- * ``{% extends "base.html" %}`` (with quotes) uses the literal value
- ``"base.html"`` as the name of the parent template to extend.
- * ``{% extends variable %}`` uses the value of ``variable``. If the variable
- evaluates to a string, Django will use that string as the name of the
- parent template. If the variable evaluates to a ``Template`` object,
- Django will use that object as the parent template.
- See :ref:`template-inheritance` for more information.
- Normally the template name is relative to the template loader's root directory.
- A string argument may also be a relative path starting with ``./`` or ``../``.
- For example, assume the following directory structure:
- .. code-block:: text
- dir1/
- template.html
- base2.html
- my/
- base3.html
- base1.html
- In ``template.html``, the following paths would be valid:
- .. code-block:: html+django
- {% extends "./base2.html" %}
- {% extends "../base1.html" %}
- {% extends "./my/base3.html" %}
- .. templatetag:: filter
- ``filter``
- ----------
- Filters the contents of the block through one or more filters. Multiple
- filters can be specified with pipes and filters can have arguments, just as
- in variable syntax.
- Note that the block includes *all* the text between the ``filter`` and
- ``endfilter`` tags.
- Sample usage:
- .. code-block:: html+django
- {% filter force_escape|lower %}
- This text will be HTML-escaped, and will appear in all lowercase.
- {% endfilter %}
- .. note::
- The :tfilter:`escape` and :tfilter:`safe` filters are not acceptable
- arguments. Instead, use the :ttag:`autoescape` tag to manage autoescaping
- for blocks of template code.
- .. templatetag:: firstof
- ``firstof``
- -----------
- Outputs the first argument variable that is not "false" (i.e. exists, is not
- empty, is not a false boolean value, and is not a zero numeric value). Outputs
- nothing if all the passed variables are "false".
- Sample usage:
- .. code-block:: html+django
- {% firstof var1 var2 var3 %}
- This is equivalent to:
- .. code-block:: html+django
- {% if var1 %}
- {{ var1 }}
- {% elif var2 %}
- {{ var2 }}
- {% elif var3 %}
- {{ var3 }}
- {% endif %}
- You can also use a literal string as a fallback value in case all
- passed variables are False:
- .. code-block:: html+django
- {% firstof var1 var2 var3 "fallback value" %}
- This tag auto-escapes variable values. You can disable auto-escaping with:
- .. code-block:: html+django
- {% autoescape off %}
- {% firstof var1 var2 var3 "<strong>fallback value</strong>" %}
- {% endautoescape %}
- Or if only some variables should be escaped, you can use:
- .. code-block:: html+django
- {% firstof var1 var2|safe var3 "<strong>fallback value</strong>"|safe %}
- You can use the syntax ``{% firstof var1 var2 var3 as value %}`` to store the
- output inside a variable.
- .. templatetag:: for
- ``for``
- -------
- Loops over each item in an array, making the item available in a context
- variable. For example, to display a list of athletes provided in
- ``athlete_list``:
- .. code-block:: html+django
- <ul>
- {% for athlete in athlete_list %}
- <li>{{ athlete.name }}</li>
- {% endfor %}
- </ul>
- You can loop over a list in reverse by using
- ``{% for obj in list reversed %}``.
- If you need to loop over a list of lists, you can unpack the values
- in each sublist into individual variables. For example, if your context
- contains a list of (x,y) coordinates called ``points``, you could use the
- following to output the list of points:
- .. code-block:: html+django
- {% for x, y in points %}
- There is a point at {{ x }},{{ y }}
- {% endfor %}
- This can also be useful if you need to access the items in a dictionary.
- For example, if your context contained a dictionary ``data``, the following
- would display the keys and values of the dictionary:
- .. code-block:: html+django
- {% for key, value in data.items %}
- {{ key }}: {{ value }}
- {% endfor %}
- Keep in mind that for the dot operator, dictionary key lookup takes precedence
- over method lookup. Therefore if the ``data`` dictionary contains a key named
- ``'items'``, ``data.items`` will return ``data['items']`` instead of
- ``data.items()``. Avoid adding keys that are named like dictionary methods if
- you want to use those methods in a template (``items``, ``values``, ``keys``,
- etc.). Read more about the lookup order of the dot operator in the
- :ref:`documentation of template variables <template-variables>`.
- The for loop sets a number of variables available within the loop:
- ========================== ===============================================
- Variable Description
- ========================== ===============================================
- ``forloop.counter`` The current iteration of the loop (1-indexed)
- ``forloop.counter0`` The current iteration of the loop (0-indexed)
- ``forloop.revcounter`` The number of iterations from the end of the
- loop (1-indexed)
- ``forloop.revcounter0`` The number of iterations from the end of the
- loop (0-indexed)
- ``forloop.first`` True if this is the first time through the loop
- ``forloop.last`` True if this is the last time through the loop
- ``forloop.parentloop`` For nested loops, this is the loop surrounding
- the current one
- ========================== ===============================================
- ``for`` ... ``empty``
- ---------------------
- The ``for`` tag can take an optional ``{% empty %}`` clause whose text is
- displayed if the given array is empty or could not be found:
- .. code-block:: html+django
- <ul>
- {% for athlete in athlete_list %}
- <li>{{ athlete.name }}</li>
- {% empty %}
- <li>Sorry, no athletes in this list.</li>
- {% endfor %}
- </ul>
- The above is equivalent to -- but shorter, cleaner, and possibly faster
- than -- the following:
- .. code-block:: html+django
- <ul>
- {% if athlete_list %}
- {% for athlete in athlete_list %}
- <li>{{ athlete.name }}</li>
- {% endfor %}
- {% else %}
- <li>Sorry, no athletes in this list.</li>
- {% endif %}
- </ul>
- .. templatetag:: if
- ``if``
- ------
- The ``{% if %}`` tag evaluates a variable, and if that variable is "true" (i.e.
- exists, is not empty, and is not a false boolean value) the contents of the
- block are output:
- .. code-block:: html+django
- {% if athlete_list %}
- Number of athletes: {{ athlete_list|length }}
- {% elif athlete_in_locker_room_list %}
- Athletes should be out of the locker room soon!
- {% else %}
- No athletes.
- {% endif %}
- In the above, if ``athlete_list`` is not empty, the number of athletes will be
- displayed by the ``{{ athlete_list|length }}`` variable.
- As you can see, the ``if`` tag may take one or several ``{% elif %}``
- clauses, as well as an ``{% else %}`` clause that will be displayed if all
- previous conditions fail. These clauses are optional.
- Boolean operators
- ~~~~~~~~~~~~~~~~~
- :ttag:`if` tags may use ``and``, ``or`` or ``not`` to test a number of
- variables or to negate a given variable:
- .. code-block:: html+django
- {% if athlete_list and coach_list %}
- Both athletes and coaches are available.
- {% endif %}
- {% if not athlete_list %}
- There are no athletes.
- {% endif %}
- {% if athlete_list or coach_list %}
- There are some athletes or some coaches.
- {% endif %}
- {% if not athlete_list or coach_list %}
- There are no athletes or there are some coaches.
- {% endif %}
- {% if athlete_list and not coach_list %}
- There are some athletes and absolutely no coaches.
- {% endif %}
- Use of both ``and`` and ``or`` clauses within the same tag is allowed, with
- ``and`` having higher precedence than ``or`` e.g.:
- .. code-block:: html+django
- {% if athlete_list and coach_list or cheerleader_list %}
- will be interpreted like::
- if (athlete_list and coach_list) or cheerleader_list:
- ...
- Use of actual parentheses in the :ttag:`if` tag is invalid syntax. If you need
- them to indicate precedence, you should use nested :ttag:`if` tags.
- :ttag:`if` tags may also use the operators ``==``, ``!=``, ``<``, ``>``,
- ``<=``, ``>=``, ``in``, ``not in``, ``is``, and ``is not`` which work as
- follows:
- ``==`` operator
- ^^^^^^^^^^^^^^^
- Equality. Example:
- .. code-block:: html+django
- {% if somevar == "x" %}
- This appears if variable somevar equals the string "x"
- {% endif %}
- ``!=`` operator
- ^^^^^^^^^^^^^^^
- Inequality. Example:
- .. code-block:: html+django
- {% if somevar != "x" %}
- This appears if variable somevar does not equal the string "x",
- or if somevar is not found in the context
- {% endif %}
- ``<`` operator
- ^^^^^^^^^^^^^^
- Less than. Example:
- .. code-block:: html+django
- {% if somevar < 100 %}
- This appears if variable somevar is less than 100.
- {% endif %}
- ``>`` operator
- ^^^^^^^^^^^^^^
- Greater than. Example:
- .. code-block:: html+django
- {% if somevar > 0 %}
- This appears if variable somevar is greater than 0.
- {% endif %}
- ``<=`` operator
- ^^^^^^^^^^^^^^^
- Less than or equal to. Example:
- .. code-block:: html+django
- {% if somevar <= 100 %}
- This appears if variable somevar is less than 100 or equal to 100.
- {% endif %}
- ``>=`` operator
- ^^^^^^^^^^^^^^^
- Greater than or equal to. Example:
- .. code-block:: html+django
- {% if somevar >= 1 %}
- This appears if variable somevar is greater than 1 or equal to 1.
- {% endif %}
- ``in`` operator
- ^^^^^^^^^^^^^^^
- Contained within. This operator is supported by many Python containers to test
- whether the given value is in the container. The following are some examples
- of how ``x in y`` will be interpreted:
- .. code-block:: html+django
- {% if "bc" in "abcdef" %}
- This appears since "bc" is a substring of "abcdef"
- {% endif %}
- {% if "hello" in greetings %}
- If greetings is a list or set, one element of which is the string
- "hello", this will appear.
- {% endif %}
- {% if user in users %}
- If users is a QuerySet, this will appear if user is an
- instance that belongs to the QuerySet.
- {% endif %}
- ``not in`` operator
- ^^^^^^^^^^^^^^^^^^^
- Not contained within. This is the negation of the ``in`` operator.
- ``is`` operator
- ^^^^^^^^^^^^^^^
- Object identity. Tests if two values are the same object. Example:
- .. code-block:: html+django
- {% if somevar is True %}
- This appears if and only if somevar is True.
- {% endif %}
- {% if somevar is None %}
- This appears if somevar is None, or if somevar is not found in the context.
- {% endif %}
- ``is not`` operator
- ^^^^^^^^^^^^^^^^^^^
- Negated object identity. Tests if two values are not the same object. This is
- the negation of the ``is`` operator. Example:
- .. code-block:: html+django
- {% if somevar is not True %}
- This appears if somevar is not True, or if somevar is not found in the
- context.
- {% endif %}
- {% if somevar is not None %}
- This appears if and only if somevar is not None.
- {% endif %}
- Filters
- ~~~~~~~
- You can also use filters in the :ttag:`if` expression. For example:
- .. code-block:: html+django
- {% if messages|length >= 100 %}
- You have lots of messages today!
- {% endif %}
- Complex expressions
- ~~~~~~~~~~~~~~~~~~~
- All of the above can be combined to form complex expressions. For such
- expressions, it can be important to know how the operators are grouped when the
- expression is evaluated - that is, the precedence rules. The precedence of the
- operators, from lowest to highest, is as follows:
- * ``or``
- * ``and``
- * ``not``
- * ``in``
- * ``==``, ``!=``, ``<``, ``>``, ``<=``, ``>=``
- (This follows Python exactly). So, for example, the following complex
- :ttag:`if` tag:
- .. code-block:: html+django
- {% if a == b or c == d and e %}
- ...will be interpreted as:
- .. code-block:: python
- (a == b) or ((c == d) and e)
- If you need different precedence, you will need to use nested :ttag:`if` tags.
- Sometimes that is better for clarity anyway, for the sake of those who do not
- know the precedence rules.
- The comparison operators cannot be 'chained' like in Python or in mathematical
- notation. For example, instead of using:
- .. code-block:: html+django
- {% if a > b > c %} (WRONG)
- you should use:
- .. code-block:: html+django
- {% if a > b and b > c %}
- .. templatetag:: ifchanged
- ``ifchanged``
- -------------
- Check if a value has changed from the last iteration of a loop.
- The ``{% ifchanged %}`` block tag is used within a loop. It has two possible
- uses.
- 1. Checks its own rendered contents against its previous state and only
- displays the content if it has changed. For example, this displays a list of
- days, only displaying the month if it changes:
- .. code-block:: html+django
- <h1>Archive for {{ year }}</h1>
- {% for date in days %}
- {% ifchanged %}<h3>{{ date|date:"F" }}</h3>{% endifchanged %}
- <a href="{{ date|date:"M/d"|lower }}/">{{ date|date:"j" }}</a>
- {% endfor %}
- 2. If given one or more variables, check whether any variable has changed.
- For example, the following shows the date every time it changes, while
- showing the hour if either the hour or the date has changed:
- .. code-block:: html+django
- {% for date in days %}
- {% ifchanged date.date %} {{ date.date }} {% endifchanged %}
- {% ifchanged date.hour date.date %}
- {{ date.hour }}
- {% endifchanged %}
- {% endfor %}
- The ``ifchanged`` tag can also take an optional ``{% else %}`` clause that
- will be displayed if the value has not changed:
- .. code-block:: html+django
- {% for match in matches %}
- <div style="background-color:
- {% ifchanged match.ballot_id %}
- {% cycle "red" "blue" %}
- {% else %}
- gray
- {% endifchanged %}
- ">{{ match }}</div>
- {% endfor %}
- .. templatetag:: include
- ``include``
- -----------
- Loads a template and renders it with the current context. This is a way of
- "including" other templates within a template.
- The template name can either be a variable or a hard-coded (quoted) string,
- in either single or double quotes.
- This example includes the contents of the template ``"foo/bar.html"``:
- .. code-block:: html+django
- {% include "foo/bar.html" %}
- Normally the template name is relative to the template loader's root directory.
- A string argument may also be a relative path starting with ``./`` or ``../``
- as described in the :ttag:`extends` tag.
- This example includes the contents of the template whose name is contained in
- the variable ``template_name``:
- .. code-block:: html+django
- {% include template_name %}
- The variable may also be any object with a ``render()`` method that accepts a
- context. This allows you to reference a compiled ``Template`` in your context.
- Additionally, the variable may be an iterable of template names, in which case
- the first that can be loaded will be used, as per
- :func:`~django.template.loader.select_template`.
- An included template is rendered within the context of the template that
- includes it. This example produces the output ``"Hello, John!"``:
- * Context: variable ``person`` is set to ``"John"`` and variable ``greeting``
- is set to ``"Hello"``.
- * Template:
- .. code-block:: html+django
- {% include "name_snippet.html" %}
- * The ``name_snippet.html`` template:
- .. code-block:: html+django
- {{ greeting }}, {{ person|default:"friend" }}!
- You can pass additional context to the template using keyword arguments:
- .. code-block:: html+django
- {% include "name_snippet.html" with person="Jane" greeting="Hello" %}
- If you want to render the context only with the variables provided (or even
- no variables at all), use the ``only`` option. No other variables are
- available to the included template:
- .. code-block:: html+django
- {% include "name_snippet.html" with greeting="Hi" only %}
- .. note::
- The :ttag:`include` tag should be considered as an implementation of
- "render this subtemplate and include the HTML", not as "parse this
- subtemplate and include its contents as if it were part of the parent".
- This means that there is no shared state between included templates --
- each include is a completely independent rendering process.
- Blocks are evaluated *before* they are included. This means that a template
- that includes blocks from another will contain blocks that have *already
- been evaluated and rendered* - not blocks that can be overridden by, for
- example, an extending template.
- .. templatetag:: load
- ``load``
- --------
- Loads a custom template tag set.
- For example, the following template would load all the tags and filters
- registered in ``somelibrary`` and ``otherlibrary`` located in package
- ``package``:
- .. code-block:: html+django
- {% load somelibrary package.otherlibrary %}
- You can also selectively load individual filters or tags from a library, using
- the ``from`` argument. In this example, the template tags/filters named ``foo``
- and ``bar`` will be loaded from ``somelibrary``:
- .. code-block:: html+django
- {% load foo bar from somelibrary %}
- See :doc:`Custom tag and filter libraries </howto/custom-template-tags>` for
- more information.
- .. templatetag:: lorem
- ``lorem``
- ---------
- Displays random "lorem ipsum" Latin text. This is useful for providing sample
- data in templates.
- Usage:
- .. code-block:: html+django
- {% lorem [count] [method] [random] %}
- The ``{% lorem %}`` tag can be used with zero, one, two or three arguments.
- The arguments are:
- =========== =============================================================
- Argument Description
- =========== =============================================================
- ``count`` A number (or variable) containing the number of paragraphs or
- words to generate (default is 1).
- ``method`` Either ``w`` for words, ``p`` for HTML paragraphs or ``b``
- for plain-text paragraph blocks (default is ``b``).
- ``random`` The word ``random``, which if given, does not use the common
- paragraph ("Lorem ipsum dolor sit amet...") when generating
- text.
- =========== =============================================================
- Examples:
- * ``{% lorem %}`` will output the common "lorem ipsum" paragraph.
- * ``{% lorem 3 p %}`` will output the common "lorem ipsum" paragraph
- and two random paragraphs each wrapped in HTML ``<p>`` tags.
- * ``{% lorem 2 w random %}`` will output two random Latin words.
- .. templatetag:: now
- ``now``
- -------
- Displays the current date and/or time, using a format according to the given
- string. Such string can contain format specifiers characters as described
- in the :tfilter:`date` filter section.
- Example:
- .. code-block:: html+django
- It is {% now "jS F Y H:i" %}
- Note that you can backslash-escape a format string if you want to use the
- "raw" value. In this example, both "o" and "f" are backslash-escaped, because
- otherwise each is a format string that displays the year and the time,
- respectively:
- .. code-block:: html+django
- It is the {% now "jS \o\f F" %}
- This would display as "It is the 4th of September".
- .. note::
- The format passed can also be one of the predefined ones
- :setting:`DATE_FORMAT`, :setting:`DATETIME_FORMAT`,
- :setting:`SHORT_DATE_FORMAT` or :setting:`SHORT_DATETIME_FORMAT`.
- The predefined formats may vary depending on the current locale and
- if :doc:`/topics/i18n/formatting` is enabled, e.g.:
- .. code-block:: html+django
- It is {% now "SHORT_DATETIME_FORMAT" %}
- You can also use the syntax ``{% now "Y" as current_year %}`` to store the
- output (as a string) inside a variable. This is useful if you want to use
- ``{% now %}`` inside a template tag like :ttag:`blocktranslate` for example:
- .. code-block:: html+django
- {% now "Y" as current_year %}
- {% blocktranslate %}Copyright {{ current_year }}{% endblocktranslate %}
- .. templatetag:: querystring
- ``querystring``
- ----------------
- .. versionadded:: 5.1
- Outputs a URL-encoded formatted query string based on the provided parameters.
- This tag requires a :class:`~django.http.QueryDict` instance, which defaults to
- :attr:`request.GET <django.http.HttpRequest.GET>` if none is provided.
- If the :class:`~django.http.QueryDict` is empty and no additional parameters
- are provided, an empty string is returned. A non-empty result includes a
- leading ``"?"``.
- .. admonition:: Using ``request.GET`` as default
- To use ``request.GET`` as the default ``QueryDict`` instance, the
- ``django.template.context_processors.request`` context processor should be
- enabled. If it's not enabled, you must either explicitly pass the
- ``request`` object into the template context, or provide a ``QueryDict``
- instance to this tag.
- Basic usage
- ~~~~~~~~~~~
- .. code-block:: html+django
- {% querystring %}
- Outputs the current query string verbatim. So if the query string is
- ``?color=green``, the output would be ``?color=green``.
- .. code-block:: html+django
- {% querystring size="M" %}
- Outputs the current query string with the addition of the ``size`` parameter.
- Following the previous example, the output would be ``?color=green&size=M``.
- Custom QueryDict
- ~~~~~~~~~~~~~~~~
- .. code-block:: html+django
- {% querystring my_query_dict %}
- You can provide a custom ``QueryDict`` to be used instead of ``request.GET``.
- So if ``my_query_dict`` is ``<QueryDict: {'color': ['blue']}>``, this outputs
- ``?color=blue``.
- Setting items
- ~~~~~~~~~~~~~
- .. code-block:: html+django
- {% querystring color="red" size="S" %}
- Adds or modifies parameters in the query string. Each keyword argument will be
- added to the query string, replacing any existing value for that key. For
- instance, if the current query string is ``?color=green``, the output will be
- ``?color=red&size=S``.
- Removing items
- ~~~~~~~~~~~~~~
- .. code-block:: html+django
- {% querystring color=None %}
- Passing ``None`` as the value removes the parameter from the query string. For
- example, if the current query string is ``?color=green&size=M``, the output
- will be ``?size=M``.
- Handling lists
- ~~~~~~~~~~~~~~
- .. code-block:: html+django
- {% querystring color=my_list %}
- If ``my_list`` is ``["red", "blue"]``, the output will be
- ``?color=red&color=blue``, preserving the list structure in the query string.
- Dynamic usage
- ~~~~~~~~~~~~~
- A common example of using this tag is to preserve the current query string when
- displaying a page of results, while adding a link to the next and previous
- pages of results. For example, if the paginator is currently on page 3, and the
- current query string is ``?color=blue&size=M&page=3``, the following code would
- output ``?color=blue&size=M&page=4``:
- .. code-block:: html+django
- {% querystring page=page.next_page_number %}
- You can also store the value in a variable. For example, if you need multiple
- links to the same page, define it as:
- .. code-block:: html+django
- {% querystring page=page.next_page_number as next_page %}
- .. templatetag:: regroup
- ``regroup``
- -----------
- Regroups a list of alike objects by a common attribute.
- This complex tag is best illustrated by way of an example: say that ``cities``
- is a list of cities represented by dictionaries containing ``"name"``,
- ``"population"``, and ``"country"`` keys:
- .. code-block:: python
- cities = [
- {"name": "Mumbai", "population": "19,000,000", "country": "India"},
- {"name": "Calcutta", "population": "15,000,000", "country": "India"},
- {"name": "New York", "population": "20,000,000", "country": "USA"},
- {"name": "Chicago", "population": "7,000,000", "country": "USA"},
- {"name": "Tokyo", "population": "33,000,000", "country": "Japan"},
- ]
- ...and you'd like to display a hierarchical list that is ordered by country,
- like this:
- * India
- * Mumbai: 19,000,000
- * Calcutta: 15,000,000
- * USA
- * New York: 20,000,000
- * Chicago: 7,000,000
- * Japan
- * Tokyo: 33,000,000
- You can use the ``{% regroup %}`` tag to group the list of cities by country.
- The following snippet of template code would accomplish this:
- .. code-block:: html+django
- {% regroup cities by country as country_list %}
- <ul>
- {% for country in country_list %}
- <li>{{ country.grouper }}
- <ul>
- {% for city in country.list %}
- <li>{{ city.name }}: {{ city.population }}</li>
- {% endfor %}
- </ul>
- </li>
- {% endfor %}
- </ul>
- Let's walk through this example. ``{% regroup %}`` takes three arguments: the
- list you want to regroup, the attribute to group by, and the name of the
- resulting list. Here, we're regrouping the ``cities`` list by the ``country``
- attribute and calling the result ``country_list``.
- ``{% regroup %}`` produces a list (in this case, ``country_list``) of
- **group objects**. Group objects are instances of
- :py:func:`~collections.namedtuple` with two fields:
- * ``grouper`` -- the item that was grouped by (e.g., the string "India" or
- "Japan").
- * ``list`` -- a list of all items in this group (e.g., a list of all cities
- with country='India').
- Because ``{% regroup %}`` produces :py:func:`~collections.namedtuple` objects,
- you can also write the previous example as:
- .. code-block:: html+django
- {% regroup cities by country as country_list %}
- <ul>
- {% for country, local_cities in country_list %}
- <li>{{ country }}
- <ul>
- {% for city in local_cities %}
- <li>{{ city.name }}: {{ city.population }}</li>
- {% endfor %}
- </ul>
- </li>
- {% endfor %}
- </ul>
- Note that ``{% regroup %}`` does not order its input! Our example relies on
- the fact that the ``cities`` list was ordered by ``country`` in the first place.
- If the ``cities`` list did *not* order its members by ``country``, the
- regrouping would naively display more than one group for a single country. For
- example, say the ``cities`` list was set to this (note that the countries are not
- grouped together):
- .. code-block:: python
- cities = [
- {"name": "Mumbai", "population": "19,000,000", "country": "India"},
- {"name": "New York", "population": "20,000,000", "country": "USA"},
- {"name": "Calcutta", "population": "15,000,000", "country": "India"},
- {"name": "Chicago", "population": "7,000,000", "country": "USA"},
- {"name": "Tokyo", "population": "33,000,000", "country": "Japan"},
- ]
- With this input for ``cities``, the example ``{% regroup %}`` template code
- above would result in the following output:
- * India
- * Mumbai: 19,000,000
- * USA
- * New York: 20,000,000
- * India
- * Calcutta: 15,000,000
- * USA
- * Chicago: 7,000,000
- * Japan
- * Tokyo: 33,000,000
- The easiest solution to this gotcha is to make sure in your view code that the
- data is ordered according to how you want to display it.
- Another solution is to sort the data in the template using the
- :tfilter:`dictsort` filter, if your data is in a list of dictionaries:
- .. code-block:: html+django
- {% regroup cities|dictsort:"country" by country as country_list %}
- Grouping on other properties
- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
- Any valid template lookup is a legal grouping attribute for the regroup
- tag, including methods, attributes, dictionary keys and list items. For
- example, if the "country" field is a foreign key to a class with
- an attribute "description," you could use:
- .. code-block:: html+django
- {% regroup cities by country.description as country_list %}
- Or, if ``country`` is a field with ``choices``, it will have a
- :meth:`~django.db.models.Model.get_FOO_display` method available as an
- attribute, allowing you to group on the display string rather than the
- ``choices`` key:
- .. code-block:: html+django
- {% regroup cities by get_country_display as country_list %}
- ``{{ country.grouper }}`` will now display the value fields from the
- ``choices`` set rather than the keys.
- .. templatetag:: resetcycle
- ``resetcycle``
- --------------
- Resets a previous `cycle`_ so that it restarts from its first item at its next
- encounter. Without arguments, ``{% resetcycle %}`` will reset the last
- ``{% cycle %}`` defined in the template.
- Example usage:
- .. code-block:: html+django
- {% for coach in coach_list %}
- <h1>{{ coach.name }}</h1>
- {% for athlete in coach.athlete_set.all %}
- <p class="{% cycle 'odd' 'even' %}">{{ athlete.name }}</p>
- {% endfor %}
- {% resetcycle %}
- {% endfor %}
- This example would return this HTML:
- .. code-block:: html
- <h1>Gareth</h1>
- <p class="odd">Harry</p>
- <p class="even">John</p>
- <p class="odd">Nick</p>
- <h1>John</h1>
- <p class="odd">Andrea</p>
- <p class="even">Melissa</p>
- Notice how the first block ends with ``class="odd"`` and the new one starts
- with ``class="odd"``. Without the ``{% resetcycle %}`` tag, the second block
- would start with ``class="even"``.
- You can also reset named cycle tags:
- .. code-block:: html+django
- {% for item in list %}
- <p class="{% cycle 'odd' 'even' as stripe %} {% cycle 'major' 'minor' 'minor' 'minor' 'minor' as tick %}">
- {{ item.data }}
- </p>
- {% ifchanged item.category %}
- <h1>{{ item.category }}</h1>
- {% if not forloop.first %}{% resetcycle tick %}{% endif %}
- {% endifchanged %}
- {% endfor %}
- In this example, we have both the alternating odd/even rows and a "major" row
- every fifth row. Only the five-row cycle is reset when a category changes.
- .. templatetag:: spaceless
- ``spaceless``
- -------------
- Removes whitespace between HTML tags. This includes tab
- characters and newlines.
- Example usage:
- .. code-block:: html+django
- {% spaceless %}
- <p>
- <a href="foo/">Foo</a>
- </p>
- {% endspaceless %}
- This example would return this HTML:
- .. code-block:: html+django
- <p><a href="foo/">Foo</a></p>
- Only space between *tags* is removed -- not space between tags and text. In
- this example, the space around ``Hello`` won't be stripped:
- .. code-block:: html+django
- {% spaceless %}
- <strong>
- Hello
- </strong>
- {% endspaceless %}
- .. templatetag:: templatetag
- ``templatetag``
- ---------------
- Outputs one of the syntax characters used to compose template tags.
- The template system has no concept of "escaping" individual characters.
- However, you can use the ``{% templatetag %}`` tag to display one of the
- template tag character combinations.
- The argument tells which template bit to output:
- ================== =======
- Argument Outputs
- ================== =======
- ``openblock`` ``{%``
- ``closeblock`` ``%}``
- ``openvariable`` ``{{``
- ``closevariable`` ``}}``
- ``openbrace`` ``{``
- ``closebrace`` ``}``
- ``opencomment`` ``{#``
- ``closecomment`` ``#}``
- ================== =======
- Sample usage:
- .. code-block:: html+django
- The {% templatetag openblock %} characters open a block.
- See also the :ttag:`verbatim` tag for another way of including these
- characters.
- .. templatetag:: url
- ``url``
- -------
- Returns an absolute path reference (a URL without the domain name) matching a
- given view and optional parameters. Any special characters in the resulting
- path will be encoded using :func:`~django.utils.encoding.iri_to_uri`.
- This is a way to output links without violating the DRY principle by having to
- hard-code URLs in your templates:
- .. code-block:: html+django
- {% url 'some-url-name' v1 v2 %}
- The first argument is a :ref:`URL pattern name <naming-url-patterns>`. It can
- be a quoted literal or any other context variable. Additional arguments are
- optional and should be space-separated values that will be used as arguments in
- the URL. The example above shows passing positional arguments. Alternatively
- you may use keyword syntax:
- .. code-block:: html+django
- {% url 'some-url-name' arg1=v1 arg2=v2 %}
- Do not mix both positional and keyword syntax in a single call. All arguments
- required by the URLconf should be present.
- For example, suppose you have a view, ``app_views.client``, whose URLconf
- takes a client ID (here, ``client()`` is a method inside the views file
- ``app_views.py``). The URLconf line might look like this:
- .. code-block:: python
- path("client/<int:id>/", app_views.client, name="app-views-client")
- If this app's URLconf is included into the project's URLconf under a path
- such as this:
- .. code-block:: python
- path("clients/", include("project_name.app_name.urls"))
- ...then, in a template, you can create a link to this view like this:
- .. code-block:: html+django
- {% url 'app-views-client' client.id %}
- The template tag will output the string ``/clients/client/123/``.
- Note that if the URL you're reversing doesn't exist, you'll get an
- :exc:`~django.urls.NoReverseMatch` exception raised, which will cause your
- site to display an error page.
- If you'd like to retrieve a URL without displaying it, you can use a slightly
- different call:
- .. code-block:: html+django
- {% url 'some-url-name' arg arg2 as the_url %}
- <a href="{{ the_url }}">I'm linking to {{ the_url }}</a>
- The scope of the variable created by the ``as var`` syntax is the
- ``{% block %}`` in which the ``{% url %}`` tag appears.
- This ``{% url ... as var %}`` syntax will *not* cause an error if the view is
- missing. In practice you'll use this to link to views that are optional:
- .. code-block:: html+django
- {% url 'some-url-name' as the_url %}
- {% if the_url %}
- <a href="{{ the_url }}">Link to optional stuff</a>
- {% endif %}
- If you'd like to retrieve a namespaced URL, specify the fully qualified name:
- .. code-block:: html+django
- {% url 'myapp:view-name' %}
- This will follow the normal :ref:`namespaced URL resolution strategy
- <topics-http-reversing-url-namespaces>`, including using any hints provided
- by the context as to the current application.
- .. warning::
- Don't forget to put quotes around the URL pattern ``name``, otherwise the
- value will be interpreted as a context variable!
- .. templatetag:: verbatim
- ``verbatim``
- ------------
- Stops the template engine from rendering the contents of this block tag.
- A common use is to allow a JavaScript template layer that collides with
- Django's syntax. For example:
- .. code-block:: html+django
- {% verbatim %}
- {{if dying}}Still alive.{{/if}}
- {% endverbatim %}
- You can also designate a specific closing tag, allowing the use of
- ``{% endverbatim %}`` as part of the unrendered contents:
- .. code-block:: html+django
- {% verbatim myblock %}
- Avoid template rendering via the {% verbatim %}{% endverbatim %} block.
- {% endverbatim myblock %}
- .. templatetag:: widthratio
- ``widthratio``
- --------------
- For creating bar charts and such, this tag calculates the ratio of a given
- value to a maximum value, and then applies that ratio to a constant.
- For example:
- .. code-block:: html+django
- <img src="bar.png" alt="Bar"
- height="10" width="{% widthratio this_value max_value max_width %}">
- If ``this_value`` is 175, ``max_value`` is 200, and ``max_width`` is 100, the
- image in the above example will be 88 pixels wide
- (because 175/200 = .875; .875 * 100 = 87.5 which is rounded up to 88).
- In some cases you might want to capture the result of ``widthratio`` in a
- variable. It can be useful, for instance, in a :ttag:`blocktranslate` like this:
- .. code-block:: html+django
- {% widthratio this_value max_value max_width as width %}
- {% blocktranslate %}The width is: {{ width }}{% endblocktranslate %}
- .. templatetag:: with
- ``with``
- --------
- Caches a complex variable under a simpler name. This is useful when accessing
- an "expensive" method (e.g., one that hits the database) multiple times.
- For example:
- .. code-block:: html+django
- {% with total=business.employees.count %}
- {{ total }} employee{{ total|pluralize }}
- {% endwith %}
- The populated variable (in the example above, ``total``) is only available
- between the ``{% with %}`` and ``{% endwith %}`` tags.
- You can assign more than one context variable:
- .. code-block:: html+django
- {% with alpha=1 beta=2 %}
- ...
- {% endwith %}
- .. note:: The previous more verbose format is still supported:
- ``{% with business.employees.count as total %}``
- .. _ref-templates-builtins-filters:
- Built-in filter reference
- =========================
- .. templatefilter:: add
- ``add``
- -------
- Adds the argument to the value.
- For example:
- .. code-block:: html+django
- {{ value|add:"2" }}
- If ``value`` is ``4``, then the output will be ``6``.
- This filter will first try to coerce both values to integers. If this fails,
- it'll attempt to add the values together anyway. This will work on some data
- types (strings, list, etc.) and fail on others. If it fails, the result will
- be an empty string.
- For example, if we have:
- .. code-block:: html+django
- {{ first|add:second }}
- and ``first`` is ``[1, 2, 3]`` and ``second`` is ``[4, 5, 6]``, then the
- output will be ``[1, 2, 3, 4, 5, 6]``.
- .. warning::
- Strings that can be coerced to integers will be **summed**, not
- concatenated, as in the first example above.
- .. templatefilter:: addslashes
- ``addslashes``
- --------------
- Adds slashes before quotes. Useful for escaping strings in CSV, for example.
- For example:
- .. code-block:: html+django
- {{ value|addslashes }}
- If ``value`` is ``"I'm using Django"``, the output will be
- ``"I\'m using Django"``.
- .. templatefilter:: capfirst
- ``capfirst``
- ------------
- Capitalizes the first character of the value. If the first character is not
- a letter, this filter has no effect.
- For example:
- .. code-block:: html+django
- {{ value|capfirst }}
- If ``value`` is ``"django"``, the output will be ``"Django"``.
- .. templatefilter:: center
- ``center``
- ----------
- Centers the value in a field of a given width.
- For example:
- .. code-block:: html+django
- "{{ value|center:"15" }}"
- If ``value`` is ``"Django"``, the output will be ``" Django "``.
- .. templatefilter:: cut
- ``cut``
- -------
- Removes all values of arg from the given string.
- For example:
- .. code-block:: html+django
- {{ value|cut:" " }}
- If ``value`` is ``"String with spaces"``, the output will be
- ``"Stringwithspaces"``.
- .. templatefilter:: date
- ``date``
- --------
- Formats a date according to the given format.
- Uses a similar format to PHP's `date()
- <https://www.php.net/manual/en/function.date.php>`_ function with some
- differences.
- .. note::
- These format characters are not used in Django outside of templates. They
- were designed to be compatible with PHP to ease transitioning for designers.
- .. _date-and-time-formatting-specifiers:
- Available format strings:
- ================ ======================================== =====================
- Format character Description Example output
- ================ ======================================== =====================
- **Day**
- ``d`` Day of the month, 2 digits with ``'01'`` to ``'31'``
- leading zeros.
- ``j`` Day of the month without leading ``'1'`` to ``'31'``
- zeros.
- ``D`` Day of the week, textual, 3 letters. ``'Fri'``
- ``l`` Day of the week, textual, long. ``'Friday'``
- ``S`` English ordinal suffix for day of the ``'st'``, ``'nd'``, ``'rd'`` or ``'th'``
- month, 2 characters.
- ``w`` Day of the week, digits without ``'0'`` (Sunday) to ``'6'`` (Saturday)
- leading zeros.
- ``z`` Day of the year. ``1`` to ``366``
- **Week**
- ``W`` ISO-8601 week number of year, with ``1``, ``53``
- weeks starting on Monday.
- **Month**
- ``m`` Month, 2 digits with leading zeros. ``'01'`` to ``'12'``
- ``n`` Month without leading zeros. ``'1'`` to ``'12'``
- ``M`` Month, textual, 3 letters. ``'Jan'``
- ``b`` Month, textual, 3 letters, lowercase. ``'jan'``
- ``E`` Month, locale specific alternative
- representation usually used for long
- date representation. ``'listopada'`` (for Polish locale, as opposed to ``'Listopad'``)
- ``F`` Month, textual, long. ``'January'``
- ``N`` Month abbreviation in Associated Press ``'Jan.'``, ``'Feb.'``, ``'March'``, ``'May'``
- style. Proprietary extension.
- ``t`` Number of days in the given month. ``28`` to ``31``
- **Year**
- ``y`` Year, 2 digits with leading zeros. ``'00'`` to ``'99'``
- ``Y`` Year, 4 digits with leading zeros. ``'0001'``, ..., ``'1999'``, ..., ``'9999'``
- ``L`` Boolean for whether it's a leap year. ``True`` or ``False``
- ``o`` ISO-8601 week-numbering year, ``'1999'``
- corresponding to the ISO-8601 week
- number (W) which uses leap weeks. See Y
- for the more common year format.
- **Time**
- ``g`` Hour, 12-hour format without leading ``'1'`` to ``'12'``
- zeros.
- ``G`` Hour, 24-hour format without leading ``'0'`` to ``'23'``
- zeros.
- ``h`` Hour, 12-hour format. ``'01'`` to ``'12'``
- ``H`` Hour, 24-hour format. ``'00'`` to ``'23'``
- ``i`` Minutes. ``'00'`` to ``'59'``
- ``s`` Seconds, 2 digits with leading zeros. ``'00'`` to ``'59'``
- ``u`` Microseconds. ``000000`` to ``999999``
- ``a`` ``'a.m.'`` or ``'p.m.'`` (Note that ``'a.m.'``
- this is slightly different than PHP's
- output, because this includes periods
- to match Associated Press style.)
- ``A`` ``'AM'`` or ``'PM'``. ``'AM'``
- ``f`` Time, in 12-hour hours and minutes, ``'1'``, ``'1:30'``
- with minutes left off if they're zero.
- Proprietary extension.
- ``P`` Time, in 12-hour hours, minutes and ``'1 a.m.'``, ``'1:30 p.m.'``, ``'midnight'``, ``'noon'``, ``'12:30 p.m.'``
- 'a.m.'/'p.m.', with minutes left off
- if they're zero and the special-case
- strings 'midnight' and 'noon' if
- appropriate. Proprietary extension.
- **Timezone**
- ``e`` Timezone name. Could be in any format,
- or might return an empty string, ``''``, ``'GMT'``, ``'-500'``, ``'US/Eastern'``, etc.
- depending on the datetime.
- ``I`` Daylight saving time, whether it's in ``'1'`` or ``'0'``
- effect or not.
- ``O`` Difference to Greenwich time in hours. ``'+0200'``
- ``T`` Time zone of this machine. ``'EST'``, ``'MDT'``
- ``Z`` Time zone offset in seconds. The ``-43200`` to ``43200``
- offset for timezones west of UTC is
- always negative, and for those east of
- UTC is always positive.
- **Date/Time**
- ``c`` ISO 8601 format. (Note: unlike other ``2008-01-02T10:30:00.000123+02:00``,
- formatters, such as "Z", "O" or "r", or ``2008-01-02T10:30:00.000123`` if the datetime is naive
- the "c" formatter will not add timezone
- offset if value is a naive datetime
- (see :class:`datetime.tzinfo`).
- ``r`` :rfc:`RFC 5322 <5322#section-3.3>` ``'Thu, 21 Dec 2000 16:01:07 +0200'``
- formatted date.
- ``U`` Seconds since the Unix Epoch
- (January 1 1970 00:00:00 UTC).
- ================ ======================================== =====================
- For example:
- .. code-block:: html+django
- {{ value|date:"D d M Y" }}
- If ``value`` is a :py:class:`~datetime.datetime` object (e.g., the result of
- ``datetime.datetime.now()``), the output will be the string
- ``'Wed 09 Jan 2008'``.
- The format passed can be one of the predefined ones :setting:`DATE_FORMAT`,
- :setting:`DATETIME_FORMAT`, :setting:`SHORT_DATE_FORMAT` or
- :setting:`SHORT_DATETIME_FORMAT`, or a custom format that uses the format
- specifiers shown in the table above. Note that predefined formats may vary
- depending on the current locale.
- Assuming that :setting:`LANGUAGE_CODE` is, for example, ``"es"``, then for:
- .. code-block:: html+django
- {{ value|date:"SHORT_DATE_FORMAT" }}
- the output would be the string ``"09/01/2008"`` (the ``"SHORT_DATE_FORMAT"``
- format specifier for the ``es`` locale as shipped with Django is ``"d/m/Y"``).
- When used without a format string, the ``DATE_FORMAT`` format specifier is
- used. Assuming the same settings as the previous example:
- .. code-block:: html+django
- {{ value|date }}
- outputs ``9 de Enero de 2008`` (the ``DATE_FORMAT`` format specifier for the
- ``es`` locale is ``r'j \d\e F \d\e Y'``). Both "d" and "e" are
- backslash-escaped, because otherwise each is a format string that displays the
- day and the timezone name, respectively.
- You can combine ``date`` with the :tfilter:`time` filter to render a full
- representation of a ``datetime`` value. E.g.:
- .. code-block:: html+django
- {{ value|date:"D d M Y" }} {{ value|time:"H:i" }}
- .. templatefilter:: default
- ``default``
- -----------
- If value evaluates to ``False``, uses the given default. Otherwise, uses the
- value.
- For example:
- .. code-block:: html+django
- {{ value|default:"nothing" }}
- If ``value`` is ``""`` (the empty string), the output will be ``nothing``.
- .. templatefilter:: default_if_none
- ``default_if_none``
- -------------------
- If (and only if) value is ``None``, uses the given default. Otherwise, uses the
- value.
- Note that if an empty string is given, the default value will *not* be used.
- Use the :tfilter:`default` filter if you want to fallback for empty strings.
- For example:
- .. code-block:: html+django
- {{ value|default_if_none:"nothing" }}
- If ``value`` is ``None``, the output will be ``nothing``.
- .. templatefilter:: dictsort
- ``dictsort``
- ------------
- Takes a list of dictionaries and returns that list sorted by the key given in
- the argument.
- For example:
- .. code-block:: html+django
- {{ value|dictsort:"name" }}
- If ``value`` is:
- .. code-block:: python
- [
- {"name": "zed", "age": 19},
- {"name": "amy", "age": 22},
- {"name": "joe", "age": 31},
- ]
- then the output would be:
- .. code-block:: python
- [
- {"name": "amy", "age": 22},
- {"name": "joe", "age": 31},
- {"name": "zed", "age": 19},
- ]
- You can also do more complicated things like:
- .. code-block:: html+django
- {% for book in books|dictsort:"author.age" %}
- * {{ book.title }} ({{ book.author.name }})
- {% endfor %}
- If ``books`` is:
- .. code-block:: python
- [
- {"title": "1984", "author": {"name": "George", "age": 45}},
- {"title": "Timequake", "author": {"name": "Kurt", "age": 75}},
- {"title": "Alice", "author": {"name": "Lewis", "age": 33}},
- ]
- then the output would be:
- .. code-block:: html+django
- * Alice (Lewis)
- * 1984 (George)
- * Timequake (Kurt)
- ``dictsort`` can also order a list of lists (or any other object implementing
- ``__getitem__()``) by elements at specified index. For example:
- .. code-block:: html+django
- {{ value|dictsort:0 }}
- If ``value`` is:
- .. code-block:: python
- [
- ("a", "42"),
- ("c", "string"),
- ("b", "foo"),
- ]
- then the output would be:
- .. code-block:: python
- [
- ("a", "42"),
- ("b", "foo"),
- ("c", "string"),
- ]
- You must pass the index as an integer rather than a string. The following
- produce empty output:
- .. code-block:: html+django
- {{ values|dictsort:"0" }}
- Ordering by elements at specified index is not supported on dictionaries.
- .. templatefilter:: dictsortreversed
- ``dictsortreversed``
- --------------------
- Takes a list of dictionaries and returns that list sorted in reverse order by
- the key given in the argument. This works exactly the same as the above filter,
- but the returned value will be in reverse order.
- .. templatefilter:: divisibleby
- ``divisibleby``
- ---------------
- Returns ``True`` if the value is divisible by the argument.
- For example:
- .. code-block:: html+django
- {{ value|divisibleby:"3" }}
- If ``value`` is ``21``, the output would be ``True``.
- .. templatefilter:: escape
- ``escape``
- ----------
- Escapes a string's HTML. Specifically, it makes these replacements:
- * ``<`` is converted to ``<``
- * ``>`` is converted to ``>``
- * ``'`` (single quote) is converted to ``'``
- * ``"`` (double quote) is converted to ``"``
- * ``&`` is converted to ``&``
- Applying ``escape`` to a variable that would normally have auto-escaping
- applied to the result will only result in one round of escaping being done. So
- it is safe to use this function even in auto-escaping environments. If you want
- multiple escaping passes to be applied, use the :tfilter:`force_escape` filter.
- For example, you can apply ``escape`` to fields when :ttag:`autoescape` is off:
- .. code-block:: html+django
- {% autoescape off %}
- {{ title|escape }}
- {% endautoescape %}
- .. admonition:: Chaining ``escape`` with other filters
- As mentioned in the :ttag:`autoescape` section, when filters including
- ``escape`` are chained together, it can result in unexpected outcomes if
- preceding filters mark a potentially unsafe string as safe due to the lack
- of escaping caused by :ttag:`autoescape` being ``off``.
- In such cases, chaining ``escape`` would not reescape strings that have
- already been marked as safe.
- This is especially important when using filters that operate on sequences,
- for example :tfilter:`join`. If you need to escape each element in a
- sequence, use the dedicated :tfilter:`escapeseq` filter.
- .. templatefilter:: escapejs
- ``escapejs``
- ------------
- Escapes characters for use as a whole JavaScript string literal, within single
- or double quotes, as below. This filter does not make the string safe for use
- in *"JavaScript template literals"* (the JavaScript backtick syntax). Any other
- uses not listed above are not supported. It is generally recommended that data
- should be passed using HTML ``data-`` attributes, or the :tfilter:`json_script`
- filter, rather than in embedded JavaScript.
- For example:
- .. code-block:: html+django
- <script>
- let myValue = '{{ value|escapejs }}'
- .. templatefilter:: escapeseq
- ``escapeseq``
- -------------
- Applies the :tfilter:`escape` filter to each element of a sequence. Useful in
- conjunction with other filters that operate on sequences, such as
- :tfilter:`join`. For example:
- .. code-block:: html+django
- {% autoescape off %}
- {{ my_list|escapeseq|join:", " }}
- {% endautoescape %}
- .. templatefilter:: filesizeformat
- ``filesizeformat``
- ------------------
- Formats the value like a 'human-readable' file size (i.e. ``'13 KB'``,
- ``'4.1 MB'``, ``'102 bytes'``, etc.).
- For example:
- .. code-block:: html+django
- {{ value|filesizeformat }}
- If ``value`` is 123456789, the output would be ``117.7 MB``.
- .. admonition:: File sizes and SI units
- Strictly speaking, ``filesizeformat`` does not conform to the International
- System of Units which recommends using KiB, MiB, GiB, etc. when byte sizes
- are calculated in powers of 1024 (which is the case here). Instead, Django
- uses traditional unit names (KB, MB, GB, etc.) corresponding to names that
- are more commonly used.
- .. templatefilter:: first
- ``first``
- ---------
- Returns the first item in a list.
- For example:
- .. code-block:: html+django
- {{ value|first }}
- If ``value`` is the list ``['a', 'b', 'c']``, the output will be ``'a'``.
- .. templatefilter:: floatformat
- ``floatformat``
- ---------------
- When used without an argument, rounds a floating-point number to one decimal
- place -- but only if there's a decimal part to be displayed. For example:
- ============ =========================== ========
- ``value`` Template Output
- ============ =========================== ========
- ``34.23234`` ``{{ value|floatformat }}`` ``34.2``
- ``34.00000`` ``{{ value|floatformat }}`` ``34``
- ``34.26000`` ``{{ value|floatformat }}`` ``34.3``
- ============ =========================== ========
- If used with a numeric integer argument, ``floatformat`` rounds a number to
- that many decimal places. For example:
- ============ ============================= ==========
- ``value`` Template Output
- ============ ============================= ==========
- ``34.23234`` ``{{ value|floatformat:3 }}`` ``34.232``
- ``34.00000`` ``{{ value|floatformat:3 }}`` ``34.000``
- ``34.26000`` ``{{ value|floatformat:3 }}`` ``34.260``
- ============ ============================= ==========
- Particularly useful is passing 0 (zero) as the argument which will round the
- float to the nearest integer.
- ============ ================================ ==========
- ``value`` Template Output
- ============ ================================ ==========
- ``34.23234`` ``{{ value|floatformat:"0" }}`` ``34``
- ``34.00000`` ``{{ value|floatformat:"0" }}`` ``34``
- ``39.56000`` ``{{ value|floatformat:"0" }}`` ``40``
- ============ ================================ ==========
- If the argument passed to ``floatformat`` is negative, it will round a number
- to that many decimal places -- but only if there's a decimal part to be
- displayed. For example:
- ============ ================================ ==========
- ``value`` Template Output
- ============ ================================ ==========
- ``34.23234`` ``{{ value|floatformat:"-3" }}`` ``34.232``
- ``34.00000`` ``{{ value|floatformat:"-3" }}`` ``34``
- ``34.26000`` ``{{ value|floatformat:"-3" }}`` ``34.260``
- ============ ================================ ==========
- If the argument passed to ``floatformat`` has the ``g`` suffix, it will force
- grouping by the :setting:`THOUSAND_SEPARATOR` for the active locale. For
- example, when the active locale is ``en`` (English):
- ============ ================================= =============
- ``value`` Template Output
- ============ ================================= =============
- ``34232.34`` ``{{ value|floatformat:"2g" }}`` ``34,232.34``
- ``34232.06`` ``{{ value|floatformat:"g" }}`` ``34,232.1``
- ``34232.00`` ``{{ value|floatformat:"-3g" }}`` ``34,232``
- ============ ================================= =============
- Output is always localized (independently of the :ttag:`{% localize off %}
- <localize>` tag) unless the argument passed to ``floatformat`` has the ``u``
- suffix, which will force disabling localization. For example, when the active
- locale is ``pl`` (Polish):
- ============ ================================= =============
- ``value`` Template Output
- ============ ================================= =============
- ``34.23234`` ``{{ value|floatformat:"3" }}`` ``34,232``
- ``34.23234`` ``{{ value|floatformat:"3u" }}`` ``34.232``
- ============ ================================= =============
- Using ``floatformat`` with no argument is equivalent to using ``floatformat``
- with an argument of ``-1``.
- .. templatefilter:: force_escape
- ``force_escape``
- ----------------
- Applies HTML escaping to a string (see the :tfilter:`escape` filter for
- details). This filter is applied *immediately* and returns a new, escaped
- string. This is useful in the rare cases where you need multiple escaping or
- want to apply other filters to the escaped results. Normally, you want to use
- the :tfilter:`escape` filter.
- For example, if you want to catch the ``<p>`` HTML elements created by
- the :tfilter:`linebreaks` filter:
- .. code-block:: html+django
- {% autoescape off %}
- {{ body|linebreaks|force_escape }}
- {% endautoescape %}
- .. templatefilter:: get_digit
- ``get_digit``
- -------------
- Given a whole number, returns the requested digit, where 1 is the right-most
- digit, 2 is the second-right-most digit, etc. Returns the original value for
- invalid input (if input or argument is not an integer, or if argument is less
- than 1). Otherwise, output is always an integer.
- For example:
- .. code-block:: html+django
- {{ value|get_digit:"2" }}
- If ``value`` is ``123456789``, the output will be ``8``.
- .. templatefilter:: iriencode
- ``iriencode``
- -------------
- Converts an IRI (Internationalized Resource Identifier) to a string that is
- suitable for including in a URL. This is necessary if you're trying to use
- strings containing non-ASCII characters in a URL.
- It's safe to use this filter on a string that has already gone through the
- :tfilter:`urlencode` filter.
- For example:
- .. code-block:: html+django
- {{ value|iriencode }}
- If ``value`` is ``"?test=I ♥ Django"``, the output will be
- ``"?test=I%20%E2%99%A5%20Django"``.
- .. templatefilter:: join
- ``join``
- --------
- Joins a list with a string, like Python's ``str.join(list)``
- For example:
- .. code-block:: html+django
- {{ value|join:" // " }}
- If ``value`` is the list ``['a', 'b', 'c']``, the output will be the string
- ``"a // b // c"``.
- .. templatefilter:: json_script
- ``json_script``
- ---------------
- Safely outputs a Python object as JSON, wrapped in a ``<script>`` tag, ready
- for use with JavaScript.
- **Argument:** The optional HTML "id" of the ``<script>`` tag.
- For example:
- .. code-block:: html+django
- {{ value|json_script:"hello-data" }}
- If ``value`` is the dictionary ``{'hello': 'world'}``, the output will be:
- .. code-block:: html
- <script id="hello-data" type="application/json">{"hello": "world"}</script>
- The resulting data can be accessed in JavaScript like this:
- .. code-block:: javascript
- const value = JSON.parse(document.getElementById('hello-data').textContent);
- XSS attacks are mitigated by escaping the characters "<", ">" and "&". For
- example if ``value`` is ``{'hello': 'world</script>&'}``, the output is:
- .. code-block:: html
- <script id="hello-data" type="application/json">{"hello": "world\\u003C/script\\u003E\\u0026amp;"}</script>
- This is compatible with a strict Content Security Policy that prohibits in-page
- script execution. It also maintains a clean separation between passive data and
- executable code.
- .. templatefilter:: last
- ``last``
- --------
- Returns the last item in a list.
- For example:
- .. code-block:: html+django
- {{ value|last }}
- If ``value`` is the list ``['a', 'b', 'c', 'd']``, the output will be the
- string ``"d"``.
- .. templatefilter:: length
- ``length``
- ----------
- Returns the length of the value. This works for both strings and lists.
- For example:
- .. code-block:: html+django
- {{ value|length }}
- If ``value`` is ``['a', 'b', 'c', 'd']`` or ``"abcd"``, the output will be
- ``4``.
- The filter returns ``0`` for an undefined variable.
- .. templatefilter:: linebreaks
- ``linebreaks``
- --------------
- Replaces line breaks in plain text with appropriate HTML; a single
- newline becomes an HTML line break (``<br>``) and a new line
- followed by a blank line becomes a paragraph break (``</p>``).
- For example:
- .. code-block:: html+django
- {{ value|linebreaks }}
- If ``value`` is ``Joel\nis a slug``, the output will be ``<p>Joel<br>is a
- slug</p>``.
- .. templatefilter:: linebreaksbr
- ``linebreaksbr``
- ----------------
- Converts all newlines in a piece of plain text to HTML line breaks
- (``<br>``).
- For example:
- .. code-block:: html+django
- {{ value|linebreaksbr }}
- If ``value`` is ``Joel\nis a slug``, the output will be ``Joel<br>is a
- slug``.
- .. templatefilter:: linenumbers
- ``linenumbers``
- ---------------
- Displays text with line numbers.
- For example:
- .. code-block:: html+django
- {{ value|linenumbers }}
- If ``value`` is:
- .. code-block:: html+django
- one
- two
- three
- the output will be:
- .. code-block:: html+django
- 1. one
- 2. two
- 3. three
- .. templatefilter:: ljust
- ``ljust``
- ---------
- Left-aligns the value in a field of a given width.
- **Argument:** field size
- For example:
- .. code-block:: html+django
- "{{ value|ljust:"10" }}"
- If ``value`` is ``Django``, the output will be ``"Django "``.
- .. templatefilter:: lower
- ``lower``
- ---------
- Converts a string into all lowercase.
- For example:
- .. code-block:: html+django
- {{ value|lower }}
- If ``value`` is ``Totally LOVING this Album!``, the output will be
- ``totally loving this album!``.
- .. templatefilter:: make_list
- ``make_list``
- -------------
- Returns the value turned into a list. For a string, it's a list of characters.
- For an integer, the argument is cast to a string before creating a list.
- For example:
- .. code-block:: html+django
- {{ value|make_list }}
- If ``value`` is the string ``"Joel"``, the output would be the list
- ``['J', 'o', 'e', 'l']``. If ``value`` is ``123``, the output will be the
- list ``['1', '2', '3']``.
- .. templatefilter:: phone2numeric
- ``phone2numeric``
- -----------------
- Converts a phone number (possibly containing letters) to its numerical
- equivalent.
- The input doesn't have to be a valid phone number. This will happily convert
- any string.
- For example:
- .. code-block:: html+django
- {{ value|phone2numeric }}
- If ``value`` is ``800-COLLECT``, the output will be ``800-2655328``.
- .. templatefilter:: pluralize
- ``pluralize``
- -------------
- Returns a plural suffix if the value is not ``1``, ``'1'``, or an object of
- length 1. By default, this suffix is ``'s'``.
- Example:
- .. code-block:: html+django
- You have {{ num_messages }} message{{ num_messages|pluralize }}.
- If ``num_messages`` is ``1``, the output will be ``You have 1 message.``
- If ``num_messages`` is ``2`` the output will be ``You have 2 messages.``
- For words that require a suffix other than ``'s'``, you can provide an alternate
- suffix as a parameter to the filter.
- Example:
- .. code-block:: html+django
- You have {{ num_walruses }} walrus{{ num_walruses|pluralize:"es" }}.
- For words that don't pluralize by simple suffix, you can specify both a
- singular and plural suffix, separated by a comma.
- Example:
- .. code-block:: html+django
- You have {{ num_cherries }} cherr{{ num_cherries|pluralize:"y,ies" }}.
- .. note:: Use :ttag:`blocktranslate` to pluralize translated strings.
- .. templatefilter:: pprint
- ``pprint``
- ----------
- A wrapper around :func:`pprint.pprint` -- for debugging, really.
- .. templatefilter:: random
- ``random``
- ----------
- Returns a random item from the given list.
- For example:
- .. code-block:: html+django
- {{ value|random }}
- If ``value`` is the list ``['a', 'b', 'c', 'd']``, the output could be ``"b"``.
- .. templatefilter:: rjust
- ``rjust``
- ---------
- Right-aligns the value in a field of a given width.
- **Argument:** field size
- For example:
- .. code-block:: html+django
- "{{ value|rjust:"10" }}"
- If ``value`` is ``Django``, the output will be ``" Django"``.
- .. templatefilter:: safe
- ``safe``
- --------
- Marks a string as not requiring further HTML escaping prior to output. When
- autoescaping is off, this filter has no effect.
- .. note::
- If you are chaining filters, a filter applied after ``safe`` can
- make the contents unsafe again. For example, the following code
- prints the variable as is, unescaped:
- .. code-block:: html+django
- {{ var|safe|escape }}
- .. templatefilter:: safeseq
- ``safeseq``
- -----------
- Applies the :tfilter:`safe` filter to each element of a sequence. Useful in
- conjunction with other filters that operate on sequences, such as
- :tfilter:`join`. For example:
- .. code-block:: html+django
- {{ some_list|safeseq|join:", " }}
- You couldn't use the :tfilter:`safe` filter directly in this case, as it would
- first convert the variable into a string, rather than working with the
- individual elements of the sequence.
- .. templatefilter:: slice
- ``slice``
- ---------
- Returns a slice of the list.
- Uses the same syntax as Python's list slicing. See the `Python documentation
- <https://docs.python.org/3/tutorial/introduction.html#lists>`_ for an
- introduction.
- Example:
- .. code-block:: html+django
- {{ some_list|slice:":2" }}
- If ``some_list`` is ``['a', 'b', 'c']``, the output will be ``['a', 'b']``.
- .. templatefilter:: slugify
- ``slugify``
- -----------
- Converts to ASCII. Converts spaces to hyphens. Removes characters that aren't
- alphanumerics, underscores, or hyphens. Converts to lowercase. Also strips
- leading and trailing whitespace.
- For example:
- .. code-block:: html+django
- {{ value|slugify }}
- If ``value`` is ``"Joel is a slug"``, the output will be ``"joel-is-a-slug"``.
- .. templatefilter:: stringformat
- ``stringformat``
- ----------------
- Formats the variable according to the argument, a string formatting specifier.
- This specifier uses the :ref:`old-string-formatting` syntax, with the exception
- that the leading "%" is dropped.
- For example:
- .. code-block:: html+django
- {{ value|stringformat:"E" }}
- If ``value`` is ``10``, the output will be ``1.000000E+01``.
- .. templatefilter:: striptags
- ``striptags``
- -------------
- Makes all possible efforts to strip all [X]HTML tags.
- For example:
- .. code-block:: html+django
- {{ value|striptags }}
- If ``value`` is ``"<b>Joel</b> <button>is</button> a <span>slug</span>"``, the
- output will be ``"Joel is a slug"``.
- .. admonition:: No safety guarantee
- Note that ``striptags`` doesn't give any guarantee about its output being
- HTML safe, particularly with non valid HTML input. So **NEVER** apply the
- ``safe`` filter to a ``striptags`` output. If you are looking for something
- more robust, consider using a third-party HTML sanitizing tool.
- .. templatefilter:: time
- ``time``
- --------
- Formats a time according to the given format.
- Given format can be the predefined one :setting:`TIME_FORMAT`, or a custom
- format, same as the :tfilter:`date` filter. Note that the predefined format
- is locale-dependent.
- For example:
- .. code-block:: html+django
- {{ value|time:"H:i" }}
- If ``value`` is equivalent to ``datetime.datetime.now()``, the output will be
- the string ``"01:23"``.
- Note that you can backslash-escape a format string if you want to use the
- "raw" value. In this example, both "h" and "m" are backslash-escaped, because
- otherwise each is a format string that displays the hour and the month,
- respectively:
- .. code-block:: html+django
- {{ value|time:"H\h i\m" }}
- This would display as "01h 23m".
- Another example:
- Assuming that :setting:`LANGUAGE_CODE` is, for example, ``"de"``, then for:
- .. code-block:: html+django
- {{ value|time:"TIME_FORMAT" }}
- the output will be the string ``"01:23"`` (The ``"TIME_FORMAT"`` format
- specifier for the ``de`` locale as shipped with Django is ``"H:i"``).
- The ``time`` filter will only accept parameters in the format string that
- relate to the time of day, not the date. If you need to format a ``date``
- value, use the :tfilter:`date` filter instead (or along with :tfilter:`time` if
- you need to render a full :py:class:`~datetime.datetime` value).
- There is one exception the above rule: When passed a ``datetime`` value with
- attached timezone information (a :ref:`time-zone-aware
- <naive_vs_aware_datetimes>` ``datetime`` instance) the ``time`` filter will
- accept the timezone-related :ref:`format specifiers
- <date-and-time-formatting-specifiers>` ``'e'``, ``'O'`` , ``'T'`` and ``'Z'``.
- When used without a format string, the ``TIME_FORMAT`` format specifier is
- used:
- .. code-block:: html+django
- {{ value|time }}
- is the same as:
- .. code-block:: html+django
- {{ value|time:"TIME_FORMAT" }}
- .. templatefilter:: timesince
- ``timesince``
- -------------
- Formats a date as the time since that date (e.g., "4 days, 6 hours").
- Takes an optional argument that is a variable containing the date to use as
- the comparison point (without the argument, the comparison point is *now*).
- For example, if ``blog_date`` is a date instance representing midnight on 1
- June 2006, and ``comment_date`` is a date instance for 08:00 on 1 June 2006,
- then the following would return "8 hours":
- .. code-block:: html+django
- {{ blog_date|timesince:comment_date }}
- Comparing offset-naive and offset-aware datetimes will return an empty string.
- Minutes is the smallest unit used, and "0 minutes" will be returned for any
- date that is in the future relative to the comparison point.
- .. templatefilter:: timeuntil
- ``timeuntil``
- -------------
- Similar to ``timesince``, except that it measures the time from now until the
- given date or datetime. For example, if today is 1 June 2006 and
- ``conference_date`` is a date instance holding 29 June 2006, then
- ``{{ conference_date|timeuntil }}`` will return "4 weeks".
- Takes an optional argument that is a variable containing the date to use as
- the comparison point (instead of *now*). If ``from_date`` contains 22 June
- 2006, then the following will return "1 week":
- .. code-block:: html+django
- {{ conference_date|timeuntil:from_date }}
- Comparing offset-naive and offset-aware datetimes will return an empty string.
- Minutes is the smallest unit used, and "0 minutes" will be returned for any
- date that is in the past relative to the comparison point.
- .. templatefilter:: title
- ``title``
- ---------
- Converts a string into titlecase by making words start with an uppercase
- character and the remaining characters lowercase. This tag makes no effort to
- keep "trivial words" in lowercase.
- For example:
- .. code-block:: html+django
- {{ value|title }}
- If ``value`` is ``"my FIRST post"``, the output will be ``"My First Post"``.
- .. templatefilter:: truncatechars
- ``truncatechars``
- -----------------
- Truncates a string if it is longer than the specified number of characters.
- Truncated strings will end with a translatable ellipsis character ("…").
- **Argument:** Number of characters to truncate to
- For example:
- .. code-block:: html+django
- {{ value|truncatechars:7 }}
- If ``value`` is ``"Joel is a slug"``, the output will be ``"Joel i…"``.
- .. templatefilter:: truncatechars_html
- ``truncatechars_html``
- ----------------------
- Similar to :tfilter:`truncatechars`, except that it is aware of HTML tags. Any
- tags that are opened in the string and not closed before the truncation point
- are closed immediately after the truncation.
- For example:
- .. code-block:: html+django
- {{ value|truncatechars_html:7 }}
- If ``value`` is ``"<p>Joel is a slug</p>"``, the output will be
- ``"<p>Joel i…</p>"``.
- Newlines in the HTML content will be preserved.
- .. admonition:: Size of input string
- Processing large, potentially malformed HTML strings can be
- resource-intensive and impact service performance. ``truncatechars_html``
- limits input to the first five million characters.
- .. templatefilter:: truncatewords
- ``truncatewords``
- -----------------
- Truncates a string after a certain number of words.
- **Argument:** Number of words to truncate after
- For example:
- .. code-block:: html+django
- {{ value|truncatewords:2 }}
- If ``value`` is ``"Joel is a slug"``, the output will be ``"Joel is …"``.
- Newlines within the string will be removed.
- .. templatefilter:: truncatewords_html
- ``truncatewords_html``
- ----------------------
- Similar to :tfilter:`truncatewords`, except that it is aware of HTML tags. Any
- tags that are opened in the string and not closed before the truncation point,
- are closed immediately after the truncation.
- This is less efficient than :tfilter:`truncatewords`, so should only be used
- when it is being passed HTML text.
- For example:
- .. code-block:: html+django
- {{ value|truncatewords_html:2 }}
- If ``value`` is ``"<p>Joel is a slug</p>"``, the output will be
- ``"<p>Joel is …</p>"``.
- Newlines in the HTML content will be preserved.
- .. admonition:: Size of input string
- Processing large, potentially malformed HTML strings can be
- resource-intensive and impact service performance. ``truncatewords_html``
- limits input to the first five million characters.
- .. templatefilter:: unordered_list
- ``unordered_list``
- ------------------
- Recursively takes a self-nested list and returns an HTML unordered list --
- WITHOUT opening and closing ``<ul>`` tags.
- The list is assumed to be in the proper format. For example, if ``var``
- contains ``['States', ['Kansas', ['Lawrence', 'Topeka'], 'Illinois']]``, then
- ``{{ var|unordered_list }}`` would return:
- .. code-block:: html+django
- <li>States
- <ul>
- <li>Kansas
- <ul>
- <li>Lawrence</li>
- <li>Topeka</li>
- </ul>
- </li>
- <li>Illinois</li>
- </ul>
- </li>
- .. templatefilter:: upper
- ``upper``
- ---------
- Converts a string into all uppercase.
- For example:
- .. code-block:: html+django
- {{ value|upper }}
- If ``value`` is ``"Joel is a slug"``, the output will be ``"JOEL IS A SLUG"``.
- .. templatefilter:: urlencode
- ``urlencode``
- -------------
- Escapes a value for use in a URL.
- For example:
- .. code-block:: html+django
- {{ value|urlencode }}
- If ``value`` is ``"https://www.example.org/foo?a=b&c=d"``, the output will be
- ``"https%3A//www.example.org/foo%3Fa%3Db%26c%3Dd"``.
- An optional argument containing the characters which should not be escaped can
- be provided.
- If not provided, the '/' character is assumed safe. An empty string can be
- provided when *all* characters should be escaped. For example:
- .. code-block:: html+django
- {{ value|urlencode:"" }}
- If ``value`` is ``"https://www.example.org/"``, the output will be
- ``"https%3A%2F%2Fwww.example.org%2F"``.
- .. templatefilter:: urlize
- ``urlize``
- ----------
- Converts URLs and email addresses in text into clickable links.
- This template tag works on links prefixed with ``http://``, ``https://``, or
- ``www.``. For example, ``https://djangocon.eu`` will get converted but
- ``djangocon.eu`` won't.
- It also supports domain-only links ending in one of the original top level
- domains (``.com``, ``.edu``, ``.gov``, ``.int``, ``.mil``, ``.net``, and
- ``.org``). For example, ``djangoproject.com`` gets converted.
- Links can have trailing punctuation (periods, commas, close-parens) and leading
- punctuation (opening parens), and ``urlize`` will still do the right thing.
- Links generated by ``urlize`` have a ``rel="nofollow"`` attribute added
- to them.
- For example:
- .. code-block:: html+django
- {{ value|urlize }}
- If ``value`` is ``"Check out www.djangoproject.com"``, the output will be
- ``"Check out <a href="http://www.djangoproject.com"
- rel="nofollow">www.djangoproject.com</a>"``.
- In addition to web links, ``urlize`` also converts email addresses into
- ``mailto:`` links. If ``value`` is
- ``"Send questions to foo@example.com"``, the output will be
- ``"Send questions to <a href="mailto:foo@example.com">foo@example.com</a>"``.
- The ``urlize`` filter also takes an optional parameter ``autoescape``. If
- ``autoescape`` is ``True``, the link text and URLs will be escaped using
- Django's built-in :tfilter:`escape` filter. The default value for
- ``autoescape`` is ``True``.
- .. note::
- If ``urlize`` is applied to text that already contains HTML markup, or to
- email addresses that contain single quotes (``'``), things won't work as
- expected. Apply this filter only to plain text.
- .. warning::
- Using ``urlize`` or ``urlizetrunc`` can incur a performance penalty, which
- can become severe when applied to user controlled values such as content
- stored in a :class:`~django.db.models.TextField`. You can use
- :tfilter:`truncatechars` to add a limit to such inputs:
- .. code-block:: html+django
- {{ value|truncatechars:500|urlize }}
- .. templatefilter:: urlizetrunc
- ``urlizetrunc``
- ---------------
- Converts URLs and email addresses into clickable links just like urlize_, but
- truncates URLs longer than the given character limit.
- **Argument:** Number of characters that link text should be truncated to,
- including the ellipsis that's added if truncation is necessary.
- For example:
- .. code-block:: html+django
- {{ value|urlizetrunc:15 }}
- If ``value`` is ``"Check out www.djangoproject.com"``, the output would be
- ``'Check out <a href="http://www.djangoproject.com"
- rel="nofollow">www.djangoproj…</a>'``.
- As with urlize_, this filter should only be applied to plain text.
- .. templatefilter:: wordcount
- ``wordcount``
- -------------
- Returns the number of words.
- For example:
- .. code-block:: html+django
- {{ value|wordcount }}
- If ``value`` is ``"Joel is a slug"``, the output will be ``4``.
- .. templatefilter:: wordwrap
- ``wordwrap``
- ------------
- Wraps words at specified line length.
- **Argument:** number of characters at which to wrap the text
- For example:
- .. code-block:: html+django
- {{ value|wordwrap:5 }}
- If ``value`` is ``Joel is a slug``, the output would be:
- .. code-block:: html+django
- Joel
- is a
- slug
- .. templatefilter:: yesno
- ``yesno``
- ---------
- Maps values for ``True``, ``False``, and (optionally) ``None``, to the strings
- "yes", "no", "maybe", or a custom mapping passed as a comma-separated list, and
- returns one of those strings according to the value:
- For example:
- .. code-block:: html+django
- {{ value|yesno:"yeah,no,maybe" }}
- ========== ====================== ===========================================
- Value Argument Outputs
- ========== ====================== ===========================================
- ``True`` ``yes``
- ``True`` ``"yeah,no,maybe"`` ``yeah``
- ``False`` ``"yeah,no,maybe"`` ``no``
- ``None`` ``"yeah,no,maybe"`` ``maybe``
- ``None`` ``"yeah,no"`` ``no`` (converts ``None`` to ``False``
- if no mapping for ``None`` is given)
- ========== ====================== ===========================================
- Internationalization tags and filters
- =====================================
- Django provides template tags and filters to control each aspect of
- :doc:`internationalization </topics/i18n/index>` in templates. They allow for
- granular control of translations, formatting, and time zone conversions.
- ``i18n``
- --------
- This library allows specifying translatable text in templates.
- To enable it, set :setting:`USE_I18N` to ``True``, then load it with
- ``{% load i18n %}``.
- See :ref:`specifying-translation-strings-in-template-code`.
- ``l10n``
- --------
- This library provides control over the localization of values in templates.
- You only need to load the library using ``{% load l10n %}``.
- See :ref:`topic-l10n-templates`.
- ``tz``
- ------
- This library provides control over time zone conversions in templates.
- Like ``l10n``, you only need to load the library using ``{% load tz %}``,
- but you'll usually also set :setting:`USE_TZ` to ``True`` so that conversion
- to local time happens by default.
- See :ref:`time-zones-in-templates`.
- Other tags and filters libraries
- ================================
- Django comes with a couple of other template-tag libraries that you have to
- enable explicitly in your :setting:`INSTALLED_APPS` setting and enable in your
- template with the :ttag:`{% load %}<load>` tag.
- ``django.contrib.humanize``
- ---------------------------
- A set of Django template filters useful for adding a "human touch" to data. See
- :doc:`/ref/contrib/humanize`.
- ``static``
- ----------
- .. templatetag:: static
- ``static``
- ~~~~~~~~~~
- To link to static files that are saved in :setting:`STATIC_ROOT` Django ships
- with a :ttag:`static` template tag. If the :mod:`django.contrib.staticfiles`
- app is installed, the tag will serve files using ``url()`` method of the
- storage specified by ``staticfiles`` in :setting:`STORAGES`. For example:
- .. code-block:: html+django
- {% load static %}
- <img src="{% static 'images/hi.jpg' %}" alt="Hi!">
- It is also able to consume standard context variables, e.g. assuming a
- ``user_stylesheet`` variable is passed to the template:
- .. code-block:: html+django
- {% load static %}
- <link rel="stylesheet" href="{% static user_stylesheet %}" media="screen">
- If you'd like to retrieve a static URL without displaying it, you can use a
- slightly different call:
- .. code-block:: html+django
- {% load static %}
- {% static "images/hi.jpg" as myphoto %}
- <img src="{{ myphoto }}" alt="Hi!">
- .. admonition:: Using Jinja2 templates?
- See :class:`~django.template.backends.jinja2.Jinja2` for information on
- using the ``static`` tag with Jinja2.
- .. templatetag:: get_static_prefix
- ``get_static_prefix``
- ~~~~~~~~~~~~~~~~~~~~~
- You should prefer the :ttag:`static` template tag, but if you need more control
- over exactly where and how :setting:`STATIC_URL` is injected into the template,
- you can use the :ttag:`get_static_prefix` template tag:
- .. code-block:: html+django
- {% load static %}
- <img src="{% get_static_prefix %}images/hi.jpg" alt="Hi!">
- There's also a second form you can use to avoid extra processing if you need
- the value multiple times:
- .. code-block:: html+django
- {% load static %}
- {% get_static_prefix as STATIC_PREFIX %}
- <img src="{{ STATIC_PREFIX }}images/hi.jpg" alt="Hi!">
- <img src="{{ STATIC_PREFIX }}images/hi2.jpg" alt="Hello!">
- .. templatetag:: get_media_prefix
- ``get_media_prefix``
- ~~~~~~~~~~~~~~~~~~~~
- Similar to the :ttag:`get_static_prefix`, ``get_media_prefix`` populates a
- template variable with the media prefix :setting:`MEDIA_URL`, e.g.:
- .. code-block:: html+django
- {% load static %}
- <body data-media-url="{% get_media_prefix %}">
- By storing the value in a data attribute, we ensure it's escaped appropriately
- if we want to use it in a JavaScript context.
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