电脑/python/Django/django学习笔记.html

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<title>django学习笔记</title>
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<meta  name="author" content="万泽(德山书生)">
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</head>
<body>
<div id="content">
<header>
<h1 class="title">django学习笔记</h1>
</header><nav id="table-of-contents">
<h2>Table of Contents</h2>
<div id="text-table-of-contents">
<ul>
<li><a href="#orgheadline1">1. 前言</a></li>
<li><a href="#orgheadline8">2. 一些命令</a>
<ul>
<li><a href="#orgheadline2">2.1. 新建一个项目</a></li>
<li><a href="#orgheadline3">2.2. 新建一个app</a></li>
<li><a href="#orgheadline4">2.3. 数据库操作</a></li>
<li><a href="#orgheadline5">2.4. 交互式环境</a></li>
<li><a href="#orgheadline6">2.5. 创建超级用户</a></li>
<li><a href="#orgheadline7">2.6. 运行网络服务器</a></li>
</ul>
</li>
<li><a href="#orgheadline10">3. url分发</a>
<ul>
<li><a href="#orgheadline9">3.1. 获取full-url</a></li>
</ul>
</li>
<li><a href="#orgheadline17">4. 模型</a>
<ul>
<li><a href="#orgheadline11">4.1. 默认创建的表格</a></li>
<li><a href="#orgheadline12">4.2. 字段类型</a></li>
<li><a href="#orgheadline13">4.3. 通用可选项</a></li>
<li><a href="#orgheadline14">4.4. 数据库中的关系</a></li>
<li><a href="#orgheadline16">4.5. ORM层的使用方法</a>
<ul>
<li><a href="#orgheadline15">4.5.1. 去重</a></li>
</ul>
</li>
</ul>
</li>
<li><a href="#orgheadline18">5. 配置</a></li>
<li><a href="#orgheadline19">6. 国际化</a></li>
<li><a href="#orgheadline21">7. 表单</a>
<ul>
<li><a href="#orgheadline20">7.1. 表单的css样式控制</a></li>
</ul>
</li>
<li><a href="#orgheadline22">8. 参考资料</a></li>
</ul>
</div>
</nav>


<div class="outline-2">
<h2 id="orgheadline1">前言</h2>
<div class="outline-text-2" id="text-1">
<p>
已经之前接触flask有一段时间了，所以关于web框架的一些基本概念这里都忽略了。
</p>
</div>
</div>


<div class="outline-2">
<h2 id="orgheadline8">一些命令</h2>
<div class="outline-text-2" id="text-2">
</div><div class="outline-3">
<h3 id="orgheadline2">新建一个项目</h3>
<div class="outline-text-3" id="text-2-1">
<p>
一开始需要新建一个项目
</p>
<pre>
django-admin startproject project-name
</pre>
</div>
</div>

<div class="outline-3">
<h3 id="orgheadline3">新建一个app</h3>
<div class="outline-text-3" id="text-2-2">
<p>
然后就是新建一个app
</p>
<pre>
python manage.py startapp app_name
</pre>
</div>
</div>

<div class="outline-3">
<h3 id="orgheadline4">数据库操作</h3>
<div class="outline-text-3" id="text-2-3">
<p>
定义模型之后，你需要运行:
</p>
<pre>
python manage.py makemigrations app_name
</pre>

<p>
这个过程将自动根据你创建的模型在数据库中创建表格。然后后面你可能改动了模型的一些内容，则要执行:
</p>

<pre>
python manage.py migrate
</pre>
<p>
也就是所谓的数据库迁移操作，不过大家都知道，数据库迁移并不是万能的，在某些情况下可能需要你手工单独处理的。
</p>
</div>
</div>

<div class="outline-3">
<h3 id="orgheadline5">交互式环境</h3>
<div class="outline-text-3" id="text-2-4">
<p>
进入python交互环境，这个和纯python交互环境的区别就是里面可以直接使用django里面的一些东西了，比如你定义的模型对象就可以直接使用了。
</p>
<pre>
python manage.py shell
</pre>

<p>
或者进入sql实现的交互环境:
</p>
<pre>
python manage.py dbshell
</pre>
</div>
</div>

<div class="outline-3">
<h3 id="orgheadline6">创建超级用户</h3>
<div class="outline-text-3" id="text-2-5">
<pre>
python manage.py createsuperuser
</pre>
<p>
创建的超级用户可以用于登录和登录django的 admin 界面。
</p>
</div>
</div>


<div class="outline-3">
<h3 id="orgheadline7">运行网络服务器</h3>
<div class="outline-text-3" id="text-2-6">
<p>
最后当然是最重要的主角了，开启网络服务器:
</p>
<pre>
python manage.py runserver
</pre>
</div>
</div>
</div>


<div class="outline-2">
<h2 id="orgheadline10">url分发</h2>
<div class="outline-text-2" id="text-3">
<p>
web框架的一个核心功能就是完成url分发工作，我们先来看下django的这块内容。
</p>

<p>
基本过程是在你的 project 的 <code>urls.py</code> 那里定义好整个项目的url分发规则。默认的内容如下:
</p>

<pre>
from django.conf.urls import url
from django.contrib import admin

urlpatterns = [
    url(r'^admin/', admin.site.urls),
]
</pre>

<p>
读者有兴趣可以先看下那个admin页，在 <code>/admin</code> 那边。请确认已经执行前面的数据库操作 <code>makemigrations</code> 和 <code>migrate</code> 了，然后已经创建超级用户了 <code>createsuperuser</code> 。这样你就可以看到django默认自动创建的admin支持页面了。
</p>

<p>
然后接下来就是类似这样的在这里插入你自己的 app的 各个 urls定义。一般如下简单写上即可:
</p>
<pre>
from django.conf.urls import include
    ....
    url(r'', include('app_name.urls')),
    ....
</pre>

<p>
下面重点来了，具体在某个app下的 <code>urls.py</code> 就会定义各个具体的url分发规则。其语法如下所示:
</p>

<pre>
from django.conf.urls import url

from . import views

urlpatterns = [
    url(r'^$', views.index, name='index'),
]
</pre>

<p>
views下面定义这具体的视图函数，这里最核心的内容就是: url这个函数和理解正则匹配规则。
</p>

<ol class="org-ol">
<li>这个正则匹配规则和Tornado框架的url分发很类似，除了在风格上，Django这边开头都不写 <code>/</code> 然后带个开头 <code>^</code> 的正则符号。然后里面都很类似。比如url可以接受参数:</li>
</ol>

<pre>
from django.conf.urls import url

from . import views

urlpatterns = [
    url(r'^add/([\d]+)/([\d]+)$', views.add, name='add'),
]
</pre>

<p>
这里参数将逐个传递个视图函数，唯一值得一提的是django的视图函数默认第一个函数是传递进去的 <code>request</code> 参量。在 <code>views.py</code> 里面的内容如下:
</p>

<div class="highlight"><pre><span></span><span class="kn">from</span> <span class="nn">django.http</span> <span class="kn">import</span> <span class="n">HttpResponse</span>
<span class="c1"># Create your views here.</span>


<span class="k">def</span> <span class="nf">add</span><span class="p">(</span><span class="n">request</span><span class="p">,</span> <span class="n">a</span><span class="p">,</span> <span class="n">b</span><span class="p">):</span>
    <span class="n">res</span> <span class="o">=</span> <span class="nb">int</span><span class="p">(</span><span class="n">a</span><span class="p">)</span> <span class="o">+</span> <span class="nb">int</span><span class="p">(</span><span class="n">b</span><span class="p">)</span>
    <span class="k">return</span> <span class="n">HttpResponse</span><span class="p">(</span><span class="nb">str</span><span class="p">(</span><span class="n">res</span><span class="p">))</span>
</pre></div>

<ol class="org-ol">
<li><code>name</code> 这个参量大体类似于flask的 <code>endpoint</code> 的概念，然后django还有的 <code>reverse</code> 函数，其大体类似于flask的 <code>url_for</code> 的概念。</li>
</ol>

<p>
比如上面视图函数的 add 对应的url我们可以如下获得:
</p>
<pre>
from django.core.urlresolvers import reverse
reverse('add',args=(1,2))
</pre>

<p>
然后在模板中有:
</p>
<pre>
&lt;a href="{% url 'add' 1 2 %}"&gt;link&lt;/a&gt;
</pre>
</div>


<div class="outline-3">
<h3 id="orgheadline9">获取full-url</h3>
<div class="outline-text-3" id="text-3-1">
<p>
上面提到的reverse函数返回的url字符串还不是完整的url，如果我们要获取全站的完整url则可以使用 <code>request.build_absolute_uri(location)</code> ，如果不指定location则是当前的url。
</p>
</div>
</div>
</div>


<div class="outline-2">
<h2 id="orgheadline17">模型</h2>
<div class="outline-text-2" id="text-4">
<p>
django的模板和sqlalchemy还是有很多地方类似的，不过还是有一些区别吧。在项目文件夹的 <code>settings.py</code> 文件里面现在有些配置需要了解了:
</p>

<dl class="org-dl">
<dt>INSTALLED_APPS</dt><dd>你需要加上你新加入的 app 的名字，这个应该和django管理各个项目模型文件有关吧。</dd>
<dt>DATABASES</dt><dd>默认会创建一个sqlite3数据库，也能满足基本的需求了，如果你想要使用mysql等数据库，则参考样例修改这里的配置。比如连接mysql的样例是:</dd>
</dl>
<pre>
DATABASES = {
    'default': {
        'ENGINE': 'django.db.backends.mysql',
        'NAME': os.environ.get("DB_NAME", "database_name"),
        'USER': os.environ.get("DB_USER", "root"),
        'PASSWORD': os.environ.get("DB_PW", ""),
        'HOST': os.environ.get("DB_HOST", "localhost"), 
        'PORT': os.environ.get("DB_PORT", "3306"),
    }
}
</pre>
</div>

<div class="outline-3">
<h3 id="orgheadline11">默认创建的表格</h3>
<div class="outline-text-3" id="text-4-1">
<p>
什么模型定义都不写，django大概就会创建十个表格，简单了解一下这些表格还是很有用的。比如说:
</p>
<dl class="org-dl">
<dt>auth_user</dt><dd>这是django用户登录管理的默认user表格，你会看到之前你创建的superuser信息就在这里。然后还有几个表格都和用户的群组权限管理相关。</dd>
<dt>django_migrations</dt><dd>存储着你的数据库迁移信息。</dd>
<dt>django_session</dt><dd>这个表格很有意思，如果你不登录你是看不到这个表格的，而且里面的内容是动态的。这就要讲到django的session机制不是基于传统的cookie，而是在这里数据库里面管理的。后面我们会继续深入了解django的session和middleware中间套件机制。</dd>
</dl>


<p>
好了，开始实际定义自己的模型了。首先基本语法如下:
</p>
<pre>
from django.db import models


class Question(models.Model):
    question_text = models.CharField(max_length=200)
    pub_date = models.DateTimeField('date published')
</pre>

<p>
这个熟悉sqlalchemy的对这段代码不会很陌生，下面进一步了解一些细节吧。
</p>
</div>
</div>


<div class="outline-3">
<h3 id="orgheadline12">字段类型</h3>
<div class="outline-text-3" id="text-4-2">
<dl class="org-dl">
<dt>IntegerField</dt><dd>整型</dd>
<dt>BigIntegerField</dt><dd>大整数</dd>
<dt>BinaryField</dt><dd>raw data</dd>
<dt>BooleanField</dt><dd>bool 值</dd>

<dt>CharField</dt><dd>定义字符串类型，常用的参数设置 <code>max_length</code> ，设置最大长度。对应的表单类型是 <code>TextInput</code> ，这个后面再说。</dd>
<dt>TextField</dt><dd>大段文字用这个，对应的表单类型是 <code>Textarea</code></dd>
<dt>DateField</dt><dd>对应python中的 <code>datetime.date</code> 对象。</dd>
<dt>TextField</dt><dd>python的 <code>datetime.time</code> object</dd>
<dt>DateTimeField</dt><dd>对应python中的 <code>datetime.datetime</code> 对象。</dd>
</dl>
<p>
一个有用的基类:
</p>

<div class="highlight"><pre><span></span><span class="k">class</span> <span class="nc">BaseModel</span><span class="p">(</span><span class="n">models</span><span class="o">.</span><span class="n">Model</span><span class="p">):</span>
    <span class="k">class</span> <span class="nc">Meta</span><span class="p">:</span>
        <span class="n">abstract</span> <span class="o">=</span> <span class="bp">True</span>

    <span class="n">updated_datetime</span> <span class="o">=</span> <span class="n">models</span><span class="o">.</span><span class="n">DateTimeField</span><span class="p">(</span><span class="n">auto_now_</span><span class="o">=</span><span class="bp">True</span><span class="p">)</span>
    <span class="n">created_datetime</span> <span class="o">=</span> <span class="n">models</span><span class="o">.</span><span class="n">DateTimeField</span><span class="p">(</span><span class="n">auto_now_add</span><span class="o">=</span><span class="bp">True</span><span class="p">)</span>
</pre></div>

<p>
后面的模型都可以继承自该基类，基类是不会创建表格的，通过 <code>class Meta</code> 然后 <code>abstract=True</code> 来获得。这里的 <code>auto_now</code> 设置为 <code>True</code> 意思是该字段每次 <code>save</code> 操作都会自动更新最新日期。 <code>auto_now_add</code> 设置为 <code>True</code> 即该对象第一次创建时设置最新的日期。
</p>

<dl class="org-dl">
<dt>DecimalField</dt><dd>对应python中的 Decimal object</dd>
<dt>DurationField</dt><dd>对应python中的 timedelta object</dd>
<dt>FilePathField</dt><dd>对应python的 float object</dd>
</dl>


<ul class="org-ul">
<li>EmailField</li>
<li>FileField</li>
<li>FilePathField</li>
<li>ImageField</li>
<li>GenericIPAddressField</li>
<li>NullBooleanField</li>

<li>PositiveIntegerField</li>
<li>PositiveSmallIntegerField</li>
<li>SlugField</li>
<li>SmallIntegerField</li>
<li>URLField</li>
<li>UUIDField</li>
</ul>
</div>
</div>


<div class="outline-3">
<h3 id="orgheadline13">通用可选项</h3>
<div class="outline-text-3" id="text-4-3">
<p>
字段声明控制中有一些通用可选项参量:
</p>
<dl class="org-dl">
<dt>default</dt><dd>设置该字段的默认值，注意default还可以接受一个函数对象。</dd>
<dt>null</dt><dd>设置为True，则该自动会自动填充sql中的NULL值，字符串类型字段最好默认空字符。</dd>
<dt>blank</dt><dd>如果设置为True，则空值也是允许的，否则需要一个明确的值。</dd>
<dt>choices</dt><dd>该字段的可选值。</dd>
</dl>

<pre>
from django.db import models

class Student(models.Model):
    YEAR_IN_SCHOOL_CHOICES = (
        (FRESHMAN, 'Freshman'),
        (SOPHOMORE, 'Sophomore'),
        (JUNIOR, 'Junior'),
        (SENIOR, 'Senior'),
    )
</pre>

<dl class="org-dl">
<dt>db_column</dt><dd>设置该字段具体在数据库中的名字。</dd>

<dt>db_index</dt><dd>设置为 <code>True</code> 则表示该字段开启索引。</dd>

<dt>primary_key</dt><dd>主键，值得一提的是 <code>pk</code> 在django的models里面有特殊含义，其一定对应的就是该表格的主键，一般推荐使用 <code>pk</code> ，因为有时某些表格的主键名字不叫 <code>id</code> 。</dd>
</dl>


<dl class="org-dl">
<dt>unique</dt><dd>唯一</dd>
<dt>unique_for_date</dt><dd>比如title字段设置:</dd>
</dl>
<pre>
unique_for_date="pub_date"
</pre>
<p>
则 title字段和 pub_date 字段都不能相同。也就是在某个日期内某个title只能有唯一值。可以看作一种 <code>unique_together</code> 的应用吧:
</p>
</div>
</div>

<div class="outline-3">
<h3 id="orgheadline14">数据库中的关系</h3>
<div class="outline-text-3" id="text-4-4">
<dl class="org-dl">
<dt>ForeignKey</dt><dd>外键引用，如果该字段的名字是user，那么实际存储在表格中的名字是user_id，然后你可以以ORM风格设置该字段如:</dd>
</dl>
<pre>
user = User(...)
</pre>

<ul class="org-ul">
<li>ManyToManyField</li>
<li>OneToOneField</li>
</ul>
</div>
</div>


<div class="outline-3">
<h3 id="orgheadline16">ORM层的使用方法</h3>
<div class="outline-text-3" id="text-4-5">
<p>
不废话，上代码，看一下就清楚了。
</p>

<pre>
from people.models import Person
Person.objects.create(name="WeizhongTu", age=24)


Person.objects.get(name="WeizhongTu")

p.save()

Person.objects.get_or_create(name="WZT", age=23) 
# 返回一个元组，第一个为Person对象，第二个为True或False, 新建时返回的是True, 已经存在时返回False.

Person.objects.all()

Person.objects.filter(name="abc")
# 等于Person.objects.filter(name__exact="abc") 名称严格等于 "abc" 的人

Person.objects.filter(name__iexact="abc") 
# 名称为 abc 但是不区分大小写，可以找到 ABC, Abc, aBC，这些都符合条件

Person.objects.filter(name__regex="^abc") # 正则表达式查询

Person.objects.filter(name__iregex="^abc")# 正则表达式不区分大小写

Person.objects.filter(name__icontains="abc") #名称中包含 "abc"，且abc不区分大小写
Person.objects.filter(name__contains="abc") # 名称中包含 "abc"的人

Person.objects.exclude(name__contains="WZ") # 排除包含 WZ 的Person对象

Person.objects.filter(name__contains="abc").exclude(age=23) 
# 找出名称含有abc, 但是排除年龄是23岁

Author.objects.all().order_by('name')
Author.objects.all().order_by('-name') # 在 column name 前加一个负号，可以实现倒序

Author.objects.filter(name__contains="WeizhongTu").filter(email="tuweizhong@163.com")
Author.objects.filter(name__contains="Wei").exclude(email="tuweizhong@163.com")

Author.objects.order_by('-id')[:20] # 反向索引
</pre>
</div>

<div class="outline-4">
<h4 id="orgheadline15">去重</h4>
<div class="outline-text-4" id="text-4-5-1">
<pre>
qs1 = Pathway.objects.filter(label__name='x')
qs2 = Pathway.objects.filter(reaction__name='A + B &gt;&gt; C')
qs3 = Pathway.objects.filter(inputer__name='WeizhongTu')
 
# 合并到一起
qs = qs1 | qs2 | qs3
这个时候就有可能出现重复的
 
# 去重方法
qs = qs.distinct()
</pre>
</div>
</div>
</div>
</div>


<div class="outline-2">
<h2 id="orgheadline18">配置</h2>
<div class="outline-text-2" id="text-5">
<p>
获取django的配置:
</p>
<pre>
from django.conf import settings
</pre>

<p>
配置里面有一些东西下面慢慢讲解之。
</p>
</div>
</div>


<div class="outline-2">
<h2 id="orgheadline19">国际化</h2>
<div class="outline-text-2" id="text-6">
<p>
国际化或者说一些语言地区的配置。
</p>
<pre>
LANGUAGE_CODE = 'zh'

TIME_ZONE = 'Asia/Shanghai'

USE_I18N = True

USE_L10N = True

USE_TZ = True
</pre>


<p>
POST 某个方法之后 redirect ，然后需要显示某个动作
</p>
</div>
</div>


<div class="outline-2">
<h2 id="orgheadline21">表单</h2>
<div class="outline-text-2" id="text-7">
<p>
首先定义一个表单对象，如下面这种写法很是简洁，但不清楚和 <code>forms.Form</code> 那种写法比较起来有何局限。
</p>

<pre>
from django.forms import ModelForm
from .models import YourModel


class Game2048InfoForm(ModelForm):

    class Meta:
        model = YourModel
        fields = ['target_field_name'...]
</pre>

<p>
在模板文件里面的使用如下:
</p>
<pre>
{{ form.name }}
</pre>
<p>
对应的就是
</p>
<pre>
&lt;input type="what" ...&gt;
</pre>

<p>
然后注意form下面要加上:
</p>
<pre>
{% csrf_token %}
</pre>

<p>
其他就常规html编写风格吧。然后视图层那边，先看一下下面这个样例代码。
</p>
<div class="highlight"><pre><span></span><span class="k">def</span> <span class="nf">index</span><span class="p">(</span><span class="n">request</span><span class="p">):</span>
    <span class="k">if</span> <span class="n">request</span><span class="o">.</span><span class="n">method</span> <span class="o">==</span> <span class="s1">&#39;POST&#39;</span><span class="p">:</span><span class="c1"># 当提交表单时</span>

        <span class="n">form</span> <span class="o">=</span> <span class="n">AddForm</span><span class="p">(</span><span class="n">request</span><span class="o">.</span><span class="n">POST</span><span class="p">)</span> <span class="c1"># form 包含提交的数据</span>

        <span class="k">if</span> <span class="n">form</span><span class="o">.</span><span class="n">is_valid</span><span class="p">():</span>
            <span class="n">form</span><span class="o">.</span><span class="n">save</span><span class="p">()</span>
        <span class="k">else</span><span class="p">:</span>
            <span class="n">logging</span><span class="o">.</span><span class="n">warning</span><span class="p">(</span><span class="s1">&#39;form invalid&#39;</span><span class="p">)</span>
    <span class="k">else</span><span class="p">:</span><span class="c1"># 当正常访问时</span>
        <span class="n">form</span> <span class="o">=</span> <span class="n">AddForm</span><span class="p">()</span>
    <span class="k">return</span> <span class="n">render</span><span class="p">(</span><span class="n">request</span><span class="p">,</span> <span class="s1">&#39;index.html&#39;</span><span class="p">,</span> <span class="p">{</span><span class="s1">&#39;form&#39;</span><span class="p">:</span> <span class="n">form</span><span class="p">})</span>
</pre></div>

<p>
如果要提交文件的话，模板form那边记得加上:
</p>
<pre>
enctype="multipart/form-data"
</pre>

<p>
然后form对象初始化如下所示:
</p>
<pre>
form = Game2048InfoForm(
    request.POST, request.FILES, instance=target_info)
</pre>

<p>
上面例子还有个很有用的Tips，就是你运行下面的 <code>form.save()</code> 。如果你希望更好的对接数据库操作，那么就如上指定具体本form对象对应数据库中的那个model instance。这个在前面可以通过 <code>get_or_create</code> 来获得。这样就可以更精确地对应响应的模型的某条记录修改那些属性了。
</p>
</div>


<div class="outline-3">
<h3 id="orgheadline20">表单的css样式控制</h3>
<div class="outline-text-3" id="text-7-1">
<p>
主要参考了 <a href="http://stackoverflow.com/questions/5827590/css-styling-in-django-forms">这个网页</a> ，该网页介绍了几种风格吧，我更喜欢下面这种写法:
</p>

<div class="highlight"><pre><span></span><span class="k">class</span> <span class="nc">Game2048InfoForm</span><span class="p">(</span><span class="n">ModelForm</span><span class="p">):</span>
    <span class="k">class</span> <span class="nc">Meta</span><span class="p">:</span>
        <span class="n">model</span> <span class="o">=</span> <span class="n">Game2048Info</span>
        <span class="n">fields</span> <span class="o">=</span> <span class="p">[</span><span class="s1">&#39;banner&#39;</span><span class="p">,</span> <span class="s1">&#39;banner_mobile&#39;</span><span class="p">,</span> <span class="s1">&#39;footer&#39;</span><span class="p">,</span> <span class="s1">&#39;footer_mobile&#39;</span><span class="p">,</span>
                  <span class="s1">&#39;title&#39;</span><span class="p">,</span> <span class="s1">&#39;info&#39;</span><span class="p">,</span> <span class="s1">&#39;guize&#39;</span><span class="p">]</span>

    <span class="k">def</span> <span class="nf">__init__</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="o">*</span><span class="n">args</span><span class="p">,</span> <span class="o">**</span><span class="n">kwargs</span><span class="p">):</span>
        <span class="nb">super</span><span class="p">(</span><span class="n">Game2048InfoForm</span><span class="p">,</span> <span class="bp">self</span><span class="p">)</span><span class="o">.</span><span class="n">__init__</span><span class="p">(</span><span class="o">*</span><span class="n">args</span><span class="p">,</span> <span class="o">**</span><span class="n">kwargs</span><span class="p">)</span>
        <span class="bp">self</span><span class="o">.</span><span class="n">fields</span><span class="p">[</span><span class="s1">&#39;title&#39;</span><span class="p">]</span><span class="o">.</span><span class="n">widget</span><span class="o">.</span><span class="n">attrs</span><span class="o">.</span><span class="n">update</span><span class="p">({</span><span class="s1">&#39;class&#39;</span> <span class="p">:</span> <span class="s1">&#39;form-control&#39;</span><span class="p">})</span>
        <span class="bp">self</span><span class="o">.</span><span class="n">fields</span><span class="p">[</span><span class="s1">&#39;info&#39;</span><span class="p">]</span><span class="o">.</span><span class="n">widget</span><span class="o">.</span><span class="n">attrs</span><span class="o">.</span><span class="n">update</span><span class="p">({</span><span class="s1">&#39;class&#39;</span> <span class="p">:</span> <span class="s1">&#39;form-control&#39;</span><span class="p">})</span>
        <span class="bp">self</span><span class="o">.</span><span class="n">fields</span><span class="p">[</span><span class="s1">&#39;guize&#39;</span><span class="p">]</span><span class="o">.</span><span class="n">widget</span><span class="o">.</span><span class="n">attrs</span><span class="o">.</span><span class="n">update</span><span class="p">({</span><span class="s1">&#39;class&#39;</span> <span class="p">:</span> <span class="s1">&#39;form-control&#39;</span><span class="p">})</span>
</pre></div>

<p>
具体我们大体可以猜到每个field都有一个widget属性，其有attrs属性，这是一个字典值。
</p>
</div>
</div>
</div>


<div class="outline-2">
<h2 id="orgheadline22">参考资料</h2>
<div class="outline-text-2" id="text-8">
<ol class="org-ol">
<li><a href="http://tutorial.djangogirls.org/zh/installation/">django girls</a></li>
<li><a href="http://www.ziqiangxuetang.com/django/django-tutorial.html">django基础教程</a></li>
</ol>
</div>
</div>
</div>
</body>
</html>