django 初识forms组件

校验字段功能

示例: 注册用户

模型:models.py

from django.db import models

# Create your models here.
class UserInfo(models.Model):
    name=models.CharField(max_length=32)
    pwd=models.CharField(max_length=32)
    email=models.EmailField()
    tel=models.CharField(max_length=32)

实验验证功能

views.py

from django.shortcuts import render,HttpResponse,redirect
from django import forms


# Create your views here.

class UserForm(forms.Form):
    name=forms.CharField(min_length=4)
    pwd=forms.CharField(min_length=4)
    re_pwd=forms.CharField(min_length=4)
    email=forms.EmailField()
    tel=forms.CharField()

def register(request):
    if request.method=='POST':
        print(request.POST)
        name=request.POST.get('name')
        form=UserForm({'name':name,'email':'123qq.com'})
        if form.is_valid():
            print(form.cleaned_data)      #如果信息正确,输出 {'name':'wang','email':'123@qq.com'}
        else:
            print(form.cleaned_data)
            print(form.errors.get('email')[0])
            print(form.errors.get('email'))
    form=UserForm()
    return render(request,'register.html',locals())

register.html

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1">
    <title>register</title>
    <link rel="stylesheet" href="https://cdn.bootcss.com/bootstrap/3.3.7/css/bootstrap.min.css"
          integrity="sha384-BVYiiSIFeK1dGmJRAkycuHAHRg32OmUcww7on3RYdg4Va+PmSTsz/K68vbdEjh4u" crossorigin="anonymous">
</head>
<body>
<form method="post">
    <div class="container">
        <div class="row">
            {% csrf_token %}
            <div class="form-group">
{#                name: <input type="text" name="name" class="form-control">#}
                name: {{ form.name }}
            </div>
            <div class="form-group">
{#                email: <input type="text" name="email" class="form-control">#}
                email: {{ form.email }}
            </div>
            <div>
                <input type="submit" class="btn btn-default pull-right">
            </div>
        </div>
    </div>
</form>
</body>
</html>

forms组件渲染标签

渲染方式一

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
   <!-- 最新版本的 Bootstrap 核心 CSS 文件 -->
    <link rel="stylesheet" href="https://cdn.bootcss.com/bootstrap/3.3.7/css/bootstrap.min.css" integrity="sha384-BVYiiSIFeK1dGmJRAkycuHAHRg32OmUcww7on3RYdg4Va+PmSTsz/K68vbdEjh4u" crossorigin="anonymous">
</head>
<body>
<h3>注册页面</h3>
<div class="container">
    <div class="row">
        <div class="col-md-6 col-lg-offset-3">

                <form action="" method="post">
                    {% csrf_token %}
                    <div>
                        <label for="">用户名</label>
                        {{ form.name }}
                    </div>
                    <div>
                        <label for="">密码</label>
                        {{ form.pwd }}
                    </div>
                    <div>
                        <label for="">确认密码</label>
                        {{ form.re_pwd }}
                    </div>
                    <div>
                        <label for=""> 邮箱</label>
                        {{ form.email }}
                    </div>

                    <input type="submit" class="btn btn-default pull-right">
                </form>
        </div>
    </div>
</div>
</body>
</html>

渲染方式二

<div class="container">
    <div class="row">
        <div class="col-md-6 col-lg-offset-3">
			<form action="" method="post">
                    {% csrf_token %}

                    {% for field in form %}
                        <div>
                            <label for="">{{ field.label }}</label>
                            {{ field }}
                        </div>
                    {% endfor %}
                    <input type="submit" class="btn btn-default pull-right">

			</form>
        </div>
    </div>
</div>

渲染方式三 (不推荐, 自定义样式不方便)

<form action="" method="post">
    {% csrf_token %}
    
    {{ form.as_p }}      // forms组件自动渲染<p></p>标签
    <input type="submit" class="btn btn-default pull-right">

</form>

forms组件渲染错误信息和参数配置

views.py

from django.shortcuts import render,HttpResponse,redirect
from django import forms
from django.forms import widgets,ValidationError
from app01.models import *


# Create your views here.

class UserForm(forms.Form):
    name=forms.CharField(min_length=4,label='姓名',
                         error_messages={'required':'该字段不能为空'},  # 当字段为空时, 自定义显示错误内容
                         widget=widgets.TextInput(attrs={'class':'form-control'}) # 标签渲染加入form-control样式
                         )
    pwd=forms.CharField(min_length=4,label='密码',
                        widget=widgets.TextInput(attrs={'class': 'form-control'}),
                        error_messages={'required': '该字段不能为空'},
                        )
    re_pwd=forms.CharField(min_length=4,label='重新输入',
                           widget=widgets.TextInput(attrs={'class': 'form-control'}),
                           error_messages={'required': '该字段不能为空'},
                           )
    email=forms.EmailField(label='邮箱',
                           widget=widgets.TextInput(attrs={'class': 'form-control'}),
                           error_messages={'required': '该字段不能为空','invalid':'格式不正确'},
                           )
    tel=forms.CharField(label='电话',
                        widget=widgets.TextInput(attrs={'class': 'form-control'}),
                        error_messages={'required': '该字段不能为空'},
                        )

def register(request):
        form=UserForm(request.POST)
        if not form.is_valid():
            errors=form.errors.get('__all__')
    else:
        form=UserForm()
    return render(request,'register.html',locals())

forms组件校验的局部钩子( clean_字段名 )

views.py

from django.shortcuts import render,HttpResponse,redirect
from django import forms
from django.forms import widgets,ValidationError
from app01.models import *


# Create your views here.

class UserForm(forms.Form):
    name=forms.CharField(min_length=4,label='姓名',
                         error_messages={'required':'该字段不能为空'},
                         widget=widgets.TextInput(attrs={'class':'form-control'})
                         )
    pwd=forms.CharField(min_length=4,label='密码',
                        widget=widgets.TextInput(attrs={'class': 'form-control'}),
                        error_messages={'required': '该字段不能为空'},
                        )
    re_pwd=forms.CharField(min_length=4,label='重新输入',
                           widget=widgets.TextInput(attrs={'class': 'form-control'}),
                           error_messages={'required': '该字段不能为空'},
                           )
    email=forms.EmailField(label='邮箱',
                           widget=widgets.TextInput(attrs={'class': 'form-control'}),
                           error_messages={'required': '该字段不能为空','invalid':'格式不正确'},
                           )
    tel=forms.CharField(label='电话',
                        widget=widgets.TextInput(attrs={'class': 'form-control'}),
                        error_messages={'required': '该字段不能为空'},
                        )

    def clean_name(self):                        # 在forms类中添加一个方法,命名规则固定 clean_字段名
        val=self.cleaned_data.get('name')        # val固定, 写死的
        ret=UserInfo.objects.filter(name=val)
        if not ret:
            return val                           # return val固定写死
        else:
            raise ValidationError('该用户已注册') # 不符合条件时触发ValidationError异常

    def clean_tel(self):
        val=self.cleaned_data.get('tel')
        ret=len(val)
        if ret == 11:
            print('true')
            return val
        else:
            raise ValidationError('格式不正确')

def register(request):
        form=UserForm(request.POST)
        if not form.is_valid():
            errors=form.errors.get('__all__')
    else:
        form=UserForm()
    return render(request,'register.html',locals())

forms组件校验的全局钩子 ( clean )

from django.shortcuts import render,HttpResponse,redirect
from django import forms
from django.forms import widgets,ValidationError
from app01.models import *


# Create your views here.

class UserForm(forms.Form):
    name=forms.CharField(min_length=4,label='姓名',
                         error_messages={'required':'该字段不能为空'},
                         widget=widgets.TextInput(attrs={'class':'form-control'})
                         )
    pwd=forms.CharField(min_length=4,label='密码',
                        widget=widgets.TextInput(attrs={'class': 'form-control'}),
                        error_messages={'required': '该字段不能为空'},
                        )
    re_pwd=forms.CharField(min_length=4,label='重新输入',
                           widget=widgets.TextInput(attrs={'class': 'form-control'}),
                           error_messages={'required': '该字段不能为空'},
                           )
    email=forms.EmailField(label='邮箱',
                           widget=widgets.TextInput(attrs={'class': 'form-control'}),
                           error_messages={'required': '该字段不能为空','invalid':'格式不正确'},
                           )
    tel=forms.CharField(label='电话',
                        widget=widgets.TextInput(attrs={'class': 'form-control'}),
                        error_messages={'required': '该字段不能为空'},
                        )

    def clean_name(self):
        val=self.cleaned_data.get('name')
        ret=UserInfo.objects.filter(name=val)
        if not ret:
            return val
        else:
            raise ValidationError('该用户已注册')

    def clean_tel(self):
        val=self.cleaned_data.get('tel')
        print(val)
        ret=len(val)
        print(ret)
        if ret == 11:
            print('true')
            return val
        else:
            raise ValidationError('格式不正确')

    def clean(self):                                       # 命名固定为clean
        pwd=self.cleaned_data.get('pwd')
        re_pwd=self.cleaned_data.get('re_pwd')
        if pwd and re_pwd:
            if pwd == re_pwd:
                return self.cleaned_data                   # 符合规则, 返回self.cleaned_data
            else:
                raise ValidationError('两次密码不一致')     # 不符合规则, 触发ValidationError异常
        else:
            return self.cleaned_data

def register(request):
    if request.method=='POST':
        form=UserForm(request.POST)
        if not form.is_valid():
            errors=form.errors.get('__all__')
    else:
        form=UserForm()
    return render(request,'register.html',locals())
原文地址:https://www.cnblogs.com/peitianwang/p/14390842.html