浅析django form(2)


浅析django form(2)

一、在views中的使用
下面从我自己做的小demo开始记录起。

1 #models.py
2 class Other2(models.Model):
3     name = models.CharField(max_length=30)
4     age = models.IntegerField()
5     email = models.EmailField()
6
7     class META:
8         db_table='Demo'

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1 #coding=utf-8
2 #forms.py
3 from django import forms
4
5 class ContactForm(forms.Form):
6     name = forms.CharField(max_length=30)
7     age = forms.IntegerField()
8     email = forms.EmailField(required=False)
9     #错误提示类，Once you’ve done that, rows will be given "error" and/or "required" classes, as needed
10     error_css_class='error'
11     required_css_class = 'required'
12
13 #自定义错误列表格式
14 from django.forms.util import ErrorList
15 class DivErrorList(ErrorList):
16     def __unicode__(self):
17         return self.as_divs()
18
19     def as_divs(self):
20         if not self:
21             return u''
22         return u'<div class="errorlist">%s</div>' % ''.join([u'<div class="error">%s</div>' %e for e in self])

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views.py
def form_test(request):
"""
----------------------------------------------
Function:    form测试
DateTime:    2013/9/9
----------------------------------------------
"""
other = Other2.objects.all()
if request.method == 'POST':
form = ContactForm(request.POST)    #绑定post数据
if form.is_valid(): #如果通过验证
#数据清理
name = form.cleaned_data['name']
age = form.cleaned_data['age']
email = form.cleaned_data['email']

Other2.objects.create(name=name,age=age,email=email)
return render_to_response('form/form.html',{'form':form,'other':other})
else:
#如果表单未被提交，则一个未绑定的表单实例被创建
form = ContactForm(initial={'name':'Hi,here','email':'@'})    #未绑定的表单
return render_to_response('form/form.html',{'form':form,'other':other})

html:
<form action='/form/form/' method='post'>{% csrf_token %}
{{form.as_table}}
<input type='submit' value='Submit' class='btn'>
</form>

<hr>
{% for obj in other %}
<p>Name: {{obj.name}}</p>
{% endfor %}

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除urls外基本上构成了django 表单的一整套。接下来就是变化子重置一些代码了。

二、自定义表单模板
上一节学了很多关于自定义表单显示的知识，在这里就运用在模板里面吧。

1、单个显示

<form action="/contact/" method="post">
{{ form.non_field_errors }}
<div class="field">
{{ form.name.errors }}
<label for="id_name">Name:</label>
{{ form.name}}
</div>

<div class="field">
{% if form.age.errors %}
{% for err in form.age.errors %}
<p>{{err|escape}}</p>
{% endfor %}
{% endif %}
<label for="id_age">Your age:</label>
{{ form.age}}
</div>

<div class="field">
{{ form.email.errors }}
<label for="id_email">Your email :</label>
{{ form.email}}
</div>

<p><input type="submit" value="Send message" /></p>
</form>

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{{form.字段名}}显示对应的字段

{{form.字段名.errors}}显示字段对应的错误提示

2、循环输出
同时可以一次循环输出所有表单字段

<form action='/form/form/' method='post'>{% csrf_token %}
{% for field in form %}
<div class='field'>
{{field.errors}}<!-- 错误提示 -->
{{field.label_tag}}:{{field}}<!-- label标签：表单字段 -->
</div>
{% endfor %}
<input type='submit' value='Submit' class='btn'>
</form>

在以上循环中{{field}}是绑定字段的实例，它也具有如下属性：

{{field.label}}:字段标签,不含html代码，如:Name

{{field.label_tag}}:含html代码的字段标签，如<label id="id_name">Name:</label>

{{field.html_name}}:字段的html名称，如：name、age

{{field.help_text}}:字段帮助文本

{{field.errors}}:字段错误列表，可循环

3、对于表单的可见与不可见
可以使用hidden_fields() and visible_fields()

对于不可见的表单字段就不显示错误信息提示，对于可见的就正常显示，如下：

<form action="/contact/" method="post">
{% for field in form.visible_fields %}
<div class="fieldWrapper">

{# Include the hidden fields in the form #}
{% if forloop.first %}
{% for hidden in form.hidden_fields %}
{{ hidden }}
{% endfor %}
{% endif %}

{{ field.errors }}
{{ field.label_tag }}: {{ field }}
</div>
{% endfor %}
<p><input type="submit" value="Send message" /></p>
</form>

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4、重复使用
如果多个模板重复使用一个表单，则可以使用{% include 'xxx.html ' %}（假设xxx.html代码中含有该表单）

<form action="/contact/" method="post">
{% include "form_snippet.html" %}
<p><input type="submit" value="Send message" /></p>
</form>

# In form_snippet.html:

{% for field in form %}
<div class="fieldWrapper">
{{ field.errors }}
{{ field.label_tag }}: {{ field }}
</div>
{% endfor %}

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三、深入表单类
不得不参考：https://docs.djangoproject.com/en/1.2/topics/forms/modelforms/

这里总结性的笔记如下：

1、从一个django model中创建表单类(form model)
这是一个趋势，django model与 form model紧密的结合。

#coding=utf-8
from django.db import models
from django.forms import ModelForm  #导入ModelForm

"""从一个django model中创建表单类(form model)"""
# Comment
class Comment(models.Model):
#....

class CommentForm(ModelForm):
class Meta:
model = Comment
#....
#Creating a form to add an comment.
form = CommentForm()
# Creating a form to change an existing comment.
>>> comment = Comment.objects.get(pk=1)
>>> form = CommentForm(instance=comment)

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注意：

(1)、字段类型的对应，django model的字段类型对应到form的字段类型，这里列举一下几个重要的：

Model field	Form field
BooleanField	BooleanField
CharField	CharField with max_length
DateField	DateField
DateTimeField	DateTimeField
FileField	FileField
ForeignKey	ModelChoiceField
IntegerField	IntegerField
ManyToManyField	ModelMultipleChoiceField
TextField	CharField with widget=forms.Textarea

ForeignKey is represented by
django.forms.ModelChoiceField, which is a
ChoiceField whose choices are a model
QuerySet.
ManyToManyField is represented by
django.forms.ModelMultipleChoiceField, which is a
MultipleChoiceField whose choices are a model
QuerySet.

(2)、对应的属性

如果model 字段 有blank=True, 则表单类中对应的要 required=False,否则required=True

表单字段的 label 被设置为model field的
verbose_name 且第一个字符大写.

表单字段的 help_text 对应models field的
help_text

如果model 字段有choices 则表单字段widget 设置
Select

实例如下：

#coding=utf-8
from django.db import models
from django import forms
from django.forms import ModelForm  #导入ModelForm

"""从一个django model中创建表单类(form model)"""
TITLE_CHOICES = (
('MR', 'Mr.'),
('MRS', 'Mrs.'),
('MS', 'Ms.'),
)

class Author(models.Model):
name = models.CharField(max_length=100)
title = models.CharField(max_length=3, choices=TITLE_CHOICES)
birth_date = models.DateField(blank=True, null=True)

def __unicode__(self):
return self.name

class Book(models.Model):
name = models.CharField(max_length=100)
authors = models.ManyToManyField(Author)

class AuthorForm(ModelForm):
class Meta:
model = Author

class BookForm(ModelForm):
class Meta:
model = Book

#以下与之对应
class AuthorForm(forms.Form):
name = forms.CharField(max_length=100)
title = forms.CharField(max_length=3,widget=forms.Select(choices=TITLE_CHOICES))    #choices
brith_date = forms.DateField(required=False)
class BookForm(forms.Form):
name = forms.CharField(max_length=100)
authors = forms.ModelMultipleChoiceField(queryset=Author.objects.all()) #ManyToManyField

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