94django_template

目录

template：... 1

设置template引擎：... 1

设置公用templates和公用static：... 2

view中使用template：... 4

去掉url和static硬编码：... 5

获取和渲染模板：... 5

内置built-in template tags和filters：... 7

自定义template filter：... 7

模板扩展extends和include包含：... 8

template：

django内置了自己的模板引擎，和jinja很像，使用简单；

django默认会在app_name/templates/下寻找模板，在app_name/templates/下再建立app_name，这样app_name/templates/app_name/下存放与该app相关的模板，因为默认django会去所有的app下找模板，可能会优先找到其它app下的模板；

默认会到app_name/static/下寻找静态文件；

设置template引擎：

TEMPLATES = [

    {

        'BACKEND': 'django.template.backends.django.DjangoTemplates',

        # 'BACKEND': 'django.template.backends.jinja2.Jinja2',

        'DIRS': [os.path.join(BASE_DIR, 'templates')],

        'APP_DIRS': True,

        'OPTIONS': {

            'context_processors': [

                'django.template.context_processors.debug',

                'django.template.context_processors.request',

                'django.contrib.auth.context_processors.auth',

                'django.contrib.messages.context_processors.messages',

            ],

        },

    },

]

context_processors are functions that receive the current HttpRequest as an argument and return a dict of data to be added to the rendering context.

设置公用templates和公用static：

mysite/mysite/settings.py

TEMPLATES = [

    {

        'BACKEND': 'django.template.backends.django.DjangoTemplates',

        'DIRS': [os.path.join(BASE_DIR, 'templates')],

        'APP_DIRS': True,

……

STATIC_URL = '/static/'

STATICFILES_DIRS = [

    os.path.join(BASE_DIR, 'static'),

]

variables:

{{ var }}、{{ dict.key }}、{{ var.attr }}、{{ var.method }}、{{ var.index }}

模板引擎支持循环、判断、过滤器：

filter：

{{ list|join:"," }}、{{ name|lower }}

{{ now | date:"Y-m-d" }}

{{ name | length }}

tags：

{% tag xxx %}{% endtag %}

{% for ... %}{% endfor %}

{# comment #}

for：

{% for person in person_list %}

<li> {{ person.name }} </li>

{% endfor %}

if：

{% if max > 10 %}

<li>max value is {{ max }} </li>

{% else %}

<li>max value is 10 </li>

{% endif %}

例：

>>> from django.template import Template,Context

>>> t = Template('My name is {{ name }}')

>>> c = Context({'name':'jowin'})   #context可以是 dict、属性、方法、tuple|list

>>> t.render(c)

'My name is jowin'

>>> t = Template('my name is {{ user.name }}')   #变量查找，dict、attr、method、list、tuple

>>> class Person:

...     def __init__(self,name):

...             self.name = name

...

>>> user = Person('jowin')

>>> user.name

'jowin'

>>> c = Context({'user':user})

>>> t.render(c)

'my name is jowin'

>>> t = Template('my name is {{ user.name }}')

>>> class Person:

...     def name(self):

...             return 'jowin'

...

>>> user = Person()

>>> user.name()

'jowin'

>>> c = Context({'user':user})

>>> t.render(c)

'my name is jowin'

view中使用template：

render源码，from django.shortcuts import render：

def render(request, template_name, context=None, content_type=None, status=None, using=None):

    """

    Returns a HttpResponse whose content is filled with the result of calling

    django.template.loader.render_to_string() with the passed arguments.

    """

    content = loader.render_to_string(template_name, context, request, using=using)

    return HttpResponse(content, content_type, status)

另，render_to_response()，老版本1.6用；

mysite/polls/views.py

from django.http import HttpResponse

from .models import Question

from django.template import loader

# def index(request):

#     latest_question_list = Question.objects.order_by('-pub_date')[:4]

#     template = loader.get_template('polls/index.html')

#     context = {'latest_question_list': latest_question_list}

#     # output = ', '.join([q.question_text for q in latest_question_list])

#     return HttpResponse(template.render(context))   #方1

def index(request):

    latest_question_list = Question.objects.order_by('-pub_date')[:4]

    context = {'latest_question_list': latest_question_list}

    return render(request, 'polls/index.html', context)   #方2

mysite/polls/templates/polls/index.html

<img src="/static/django.png">   #mysite/polls/static/django.png

{% if latest_question_list %}

    <ul>

        {% for question in latest_question_list %}

        <li><a href="/polls/{{ question.id }}/">{{ question.question_text }}</a></li>

        {% endfor %}

    </ul>

{% endif %}

去掉url和static硬编码：

mysite/polls/templates/polls/index.html

{% load static %}

<img src="{% static 'django.png' %}">

{% if latest_question_list %}

    <ul>

        {% for question in latest_question_list %}

        <!--<li><a href="/polls/{{ question.id }}/">{{ question.question_text }}</a></li>-->

        <li><a href="{% url 'detail' question.id %}">{{ question.question_text }}</a></li>

        {% endfor %}

    </ul>

{% endif %}

注：

{% url 'detail' question.id %}   #app的urls.py中定义的name有关；app namespace改后，'detail'改为'polls:detail'；

获取和渲染模板：

方1：

from django.template.loader import get_template

def get_template(template_name, using=None):   #返回一个模板对象，再使用模板对象的类方法Template中的render()渲染

    """

    Loads and returns a template for the given name.

    Raises TemplateDoesNotExist if no such template exists.

    """

    chain = []

    engines = _engine_list(using)

    for engine in engines:

        try:

            return engine.get_template(template_name)

        except TemplateDoesNotExist as e:

            chain.append(e)

    raise TemplateDoesNotExist(template_name, chain=chain)

class Template(object):

    def __init__(self, template_string, origin=None, name=None, engine=None):

                   ……

    def _render(self, context):

        return self.nodelist.render(context)

    def render(self, context):

        "Display stage -- can be called many times"

        with context.render_context.push_state(self):

            if context.template is None:

                with context.bind_template(self):

                    context.template_name = self.name

                    return self._render(context)

            else:

                return self._render(context)

方2：

from django.shortcuts import render

def render(request, template_name, context=None, content_type=None, status=None, using=None):

    """

    Returns a HttpResponse whose content is filled with the result of calling

    django.template.loader.render_to_string() with the passed arguments.

    """

    content = loader.render_to_string(template_name, context, request, using=using)

    return HttpResponse(content, content_type, status)

方3：

from django.template.loader import render_to_string

def render_to_string(template_name, context=None, request=None, using=None):

    """

    Loads a template and renders it with a context. Returns a string.

    template_name may be a string or a list of strings.

    """

    if isinstance(template_name, (list, tuple)):

        template = select_template(template_name, using=using)

    else:

        template = get_template(template_name, using=using)

    return template.render(context, request)

内置built-in template tags和filters：

block   #Defines a block that can be overridden by child templates.，{% block custom_title %}首页{% endblock %}

csrf_token   #html的form标签中使用，{% csrf_tokne %}

extends   #模板扩展，{% extends 'base.html' %}

include   #模板包含，{% include 'pagination.html' %}

url   # <h4><a href="{% url 'article_detail' article.id %}">{{ article.title }}</a></h4>

filter

for

for ... empty

if

例：

{% for ad in ads %}

<a href="{{ ad.callback_url }}" target="_blank">

    <img id="slide-img-{{ forloop.counter }}" src="{{ MEDIA_URL }}{{ ad.image_url }}" alt="" />

</a>

{% endfor %}

过滤器使用格式：

{{ 变量|过滤器:参数 }}

add   # <div class="module1_{{ forloop.counter|add:2 }} box">

center

date   # <div>{{ article.date_publish|date:'d' }}</div>，{{ article.date_publish|date:'Y-m-d' }}

default

dictsort

dictsortreversed

filesizeformat

length

last

ljust

lower

random

rjust

safe   # 告诉browser，这个变量是安全的，可以渲染，没必要显示纯文本，{{ article.content | safe }}

title

truncatewords   #如果后端传的数据太多，只显示一部分，{{ value|truncatewords:3 }}，截取3个单词

i18n

tz

static   #{% load static %}吗{% load staticfiles %}

get_static_prefix   # <img src="{% get_static_prefix %}images/hi.jpg" alt="Hi!">

get_media_prefix

例：

{% extends "base.html" %}

{% block content %}

         <h3>Publishers</h3>

         <ul>

                   {% for publisher in object_list %}

                   <li>{{ publisher.name }}</li>

                   {% endfor %}

         </ul>

{% endblock %}

{% ifequal a b %} ... {% endifequal %} is an obsolete way to write {% if a == b %} ... {% endif %}

Likewise,

{% ifnotequal a b %} ... {% endifnotequal %} is superseded by {% if a != b %} ... {% endif %}

The ifequal and ifnotequal tags will be deprecated in a future release.

{% for current_org in hot_orgs %}

    <dl>

        <dt class="num fl">{{ forloop.counter }}</dt>   #The current iteration of the loop (1-indexed)

        <dd>

            <a href="/company/2/"><h2>{{ current_org }}</h2></a>

            <p>{{ current_org.address }}</p>

        </dd>

    </dl>

{% endfor%}

自定义template filter：

django寻找自定义filter的目录是app_name/templatetags/；

例：

mysite/polls/templatetags/mytags.py

from django import template

register = template.Library()

@register.filter

def lower(text):

    return text.lower()

@register.filter

def question_choice_count(question):

    return question.choice_set.count()

@register.filter

def question_choice_count_add(question, num):

    return question.choice_set.count() + int(num)

mysite/polls/templates/polls/index.html

{% load static %}

{% load mytags %}

<img src="{% static 'django.png' %}">

{% if latest_question_list %}

    <ul>

        {% for question in latest_question_list %}

        <!--<li><a href="/polls/{{ question.id }}/">{{ question.question_text }}</a></li>-->

        <li><a href="{% url 'polls:detail' question.id %}">{{ question.question_text }}</a>

        -- {{ question|question_choice_count }}</li>

        {% endfor %}

    </ul>

{% endif %}

模板扩展extends和include包含：

实现网页布局；

extends是继承模板，然后自定义可设置的block；

include是导入一个模板片段到该位置；