一分钟学会Django的表单
来源：岁月联盟
时间：2012-02-05
from django import forms
class ContactForm(forms.Form):
subject = forms.CharField()
email = forms.EmailField(required=False, label='Your e-mail address') #define label
message = forms.CharField(widget=forms.Textarea ) #define output format
#define custom check method, nameing rule clean_attname(), executed after default clean(),e.g, is_valid() method.
#we can set cleand_data to the python value we want, so the value is better returned or we will lost the value.
def clean_message(self):
message = self.cleaned_data['message']
num_words = len(message.split())
if num_words < 4:
raise forms.ValidationError("Not enough words!")
return message
[python] view plaincopy
# views.py
from django.shortcuts import render_to_response
from mysite.contact.forms import ContactForm
def contact(request):
if request.method == 'POST':
form = ContactForm(request.POST)
if form.is_valid(): #if valid, then cleaned_data attr is gen.
cd = form.cleaned_data
send_mail(
cd['subject'],
cd['message'],
cd.get('email', 'noreply@example.com'),
['siteowner@example.com'],
)
return HttpResponseRedirect('/contact/thanks/')
else:
form = ContactForm() #or add an initial value
form = ContactForm(initial={'subject': 'I love your site!'})
return render_to_response('contact_form.html', {'form': form})
# contact_form.html
<html>
<head>
<title>Contact us</title>
<style type="text/css">
ul.errorlist {
margin: 0;
padding: 0;}
.errorlist li {
background-color: red;
color: white;
display: block;
font-size: 10px;
margin: 0 0 3px;
padding: 4px 5px;}
</style>
</head>
<body>
<h1>Contact us</h1>
{% if form.errors %}
<p style="color: red;">
Please correct the error{{ form.errors|pluralize }} below.
</p>
{% endif %}
<form action="" method="post">
<div class="field"> #define you own style
{{ form.subject.errors }}
<label for="id_subject">Subject:</label>
{{ form.subject }}
</div>
<div class="field">
{{ form.email.errors }}
<label for="id_email">Your e-mail address:</label>
{{ form.email }}
</div>
<div class="field">
{{ form.message.errors }}
<label for="id_message">Message:</label>
{{ form.message }}
</div>
<input type="submit" value="Submit">
</form>
<!--{{ form.message.errors }} 会在<ul class="errorlist"> 里面显示，如果字段是合法的，或者form没有被绑定，就显示一个空字符串。-->
<!-- 我们还可以把form.message.errors 当作一个布尔值或者当它是list在上面做迭代， 例如：-->
<div class="field{% if form.message.errors %} errors{% endif %}">
{% if form.message.errors %}
<ul>
{% for error in form.message.errors %}
<li><strong>{{ error }}</strong></li>
{% endfor %}
</ul>
{% endif %}
<label for="id_message">Message:</label>
{{ form.message }}
</div>
<!--在校验失败的情况下, www.2cto.com这段代码会在包含错误字段的div的class属性中增加一个”errors”，在一个有序列表中显示错误信息。-->
</body>
</html>
摘自 ZhangIt的专栏
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