使用context来传递数据，一个context是一系列变量

页面设计工作和python代码分离，所以我们引用模板来实现这个功能。

一、模板实例

下面是一个模板的实例：

[python]
<html>
<head><title>Ordering notice</title></head>
<body>
<h1>Ordering notice</h1>
Dear {{ person_name }},
Thanks for placing an order from {{ company }}. It's scheduled to
ship on {{ ship_date|date:"F j, Y" }}.
Here are the items you've ordered:
<ul>
{% for item in item_list %}
<li>{{ item }}</li>
{% endfor %}
</ul>
{% if ordered_warranty %}
Your warranty information will be included in the packaging.
{% else %}
You didn't order a warranty, so you're on your own when
the products inevitably stop working.
{% endif %}
Sincerely, {{ company }}
</body>
</html>
<html>
<head><title>Ordering notice</title></head>

<body>

<h1>Ordering notice</h1>

Dear {{ person_name }},

Thanks for placing an order from {{ company }}. It's scheduled to
ship on {{ ship_date|date:"F j, Y" }}.

Here are the items you've ordered:

<ul>
{% for item in item_list %}
<li>{{ item }}</li>
{% endfor %}
</ul>
{% if ordered_warranty %}
Your warranty information will be included in the packaging.
{% else %}
You didn't order a warranty, so you're on your own when
the products inevitably stop working.
{% endif %}

Sincerely, {{ company }}

</body>
</html>
分析其中的一些元素：

（1）用大括号括起来的称作：变量，需要对它进行赋值

（2）用大括号和百分号括起来的是：模板标签，即通知模板系统完成某些工作的标签。上文中有两个模板标签：for和if分别实现循环和判断。

（3）第二段有个filter过滤器的使用：

{{ ship_date|date:"F j, Y" }
它是将变量ship_date传递给过滤器date，同时指定参数，过滤器按照参数输出。
二、使用模板

1、基本流程：

（1）用原始的模板代码创建一个Template对象

（2）创建一个Context对象，完成对模板对象中的变量赋值

（3）调用模板对象的render方法，将（2）步生成的context对象作为参数，填充模板，同时返回基于模板的展现字符串，这时其中的变量已经被替换。

实例：

[python]
>>> from django import template
>>> t = template.Template('My name is {{ name }}.')
>>> c = template.Context({'name': 'Adrian'})
>>> print t.render(c)
My name is Adrian.
>>> c = template.Context({'name': 'Fred'})
>>> print t.render(c)
My name is Fred.
>>> from django import template
>>> t = template.Template('My name is {{ name }}.')
>>> c = template.Context({'name': 'Adrian'})
>>> print t.render(c)
My name is Adrian.
>>> c = template.Context({'name': 'Fred'})
>>> print t.render(c)
My name is Fred.
2、创建模板对象

转到mysite所在的目录，输入

[python]
python manage.py shell
python manage.py shell
为什么我们运行pythonmanage.pyshell而不是python的。这两个命令都会启动交互解释器，但是manage.pyshell命令有一个重要的不同：在启动解释器之前，它告诉Django使用哪个设置文件。 Django框架的大部分子系统，包括模板系统，都依赖于配置文件；如果Django不知道使用哪个配置文件，这些系统将不能工作。
[python]
>>> from django import template
>>> t = template.Template('My name is {{ name }}.')
>>> print t
<django.template.base.Template object at 0x0220EBD0>
>>> from django import template
>>> t = template.Template('My name is {{ name }}.')
>>> print t
<django.template.base.Template object at 0x0220EBD0>每次创建一个template对象，打印出来的地址都不同。

3、模板渲染

即，对模板内的变量、标签赋值。

使用context来传递数据，一个context是一系列变量和他们的值的集合，然后用template的render方法传递context填充模板。

[python]
>>> from django import template
>>> t = template.Template('My name is {{ name }}.')
>>> c = template.Context('name': 'Jim')
>>> t.render(c)2881064151
u'My name is Jim.'
>>> from django import template
>>> t = template.Template('My name is {{ name }}.')
>>> c = template.Context('name': 'Jim')
>>> t.render(c)
u'My name is Jim.'
实例：
[python]
>>> from django.template import Template, Context
>>> raw_template = """Dear {{ person_name }},
...
... Thanks for placing an order from {{ company }}. It's scheduled to
... ship on {{ ship_date|date:"F j, Y" }}.
...
... {% if ordered_warranty %}
... Your warranty information will be included in the packaging.
... {% else %}
... You didn't order a warranty, so you're on your own when
... the products inevitably stop working.
... {% endif %}
...
... Sincerely, {{ company }}"""
>>> t = Template(raw_template)
>>> import datetime
>>> c = Context({'person_name': 'John Smith',
... 'company': 'Outdoor Equipment',
... 'ship_date': datetime.date(2009, 4, 2),
... 'ordered_warranty': False})
>>> t.render(c)
u"Dear John Smith, Thanks for placing an order from Outdoor
Equipment. It's scheduled to ship on April 2, 2009. You
didn't order a warranty, so you're on your own when the products
inevitably stop working. Sincerely, Outdoor Equipment
"
>>> from django.template import Template, Context
>>> raw_template = """Dear {{ person_name }},
...
... Thanks for placing an order from {{ company }}. It's scheduled to
... ship on {{ ship_date|date:"F j, Y" }}.
...
... {% if ordered_warranty %}
... Your warranty information will be included in the packaging.
... {% else %}
... You didn't order a warranty, so you're on your own when
... the products inevitably stop working.
... {% endif %}
...
... Sincerely, {{ company }}"""
>>> t = Template(raw_template)
>>> import datetime
>>> c = Context({'person_name': 'John Smith',
... 'company': 'Outdoor Equipment',
... 'ship_date': datetime.date(2009, 4, 2),
... 'ordered_warranty': False})
>>> t.render(c)
u"Dear John Smith, Thanks for placing an order from Outdoor
Equipment. It's scheduled to ship on April 2, 2009. You
didn't order a warranty, so you're on your own when the products
inevitably stop working. Sincerely, Outdoor Equipment
"

输出的结果没有按照显示换行，这和python解释器有关，它会按照真实内容显示，如果想显示出换行，使用print t.render(c)

4、一个模板多个渲染
一旦定义了一个模板，就可以渲染多个context
[python]
>>> from django.template import Template, Context
>>> t = Template('My name is {{ name }}.')
>>> print t.render(Context{'name': 'Jim'})
My name is Jim.
>>> print t.render(Context{'name': 'Pat'})
My name is Pat.
>>> from django.template import Template, Context
>>> t = Template('My name is {{ name }}.')
>>> print t.render(Context{'name': 'Jim'})
My name is Jim.
>>> print t.render(Context{'name': 'Pat'})
My name is Pat.
[python]
>>> from django.template import Template, Context
>>> t = Template('Hello, {{ name }}')
>>> for name in ('John', 'Juile', 'pat'):
... print t.render(Context({'name': name}))
...
Hello, John
Hello, Juile
Hello, pat
>>> from django.template import Template, Context
>>> t = Template('Hello, {{ name }}')
>>> for name in ('John', 'Juile', 'pat'):
... print t.render(Context({'name': name}))
...
Hello, John
Hello, Juile
Hello, pat