前一章节介绍了django中的表单,本章节继续介绍表单,但是本章节是基于数据模型来使用的表单,因为我们也称之为模型表单

一、使用模型表单的主要步骤

• 1、定义数据模型

  from django.db import models
  from django.core import validators
  
  
  class ArticleModel(models.Model):
      """
      定义文章的数据模型
      """
      title = models.CharField(max_length=10, validators=[validators.MinValueValidator(limit_value=3)], verbose_name='标题')
      content = models.TextField(verbose_name='内容')
      author = models.CharField(max_length=10, verbose_name='作者')
      category = models.CharField(max_length=10, verbose_name='分类')
      create_time = models.DateTimeField(auto_now_add=True, verbose_name='创建时间')
      update_time = models.DateTimeField(auto_now=True, verbose_name='修改时间')
  
      class Meta(object):
          db_table = 'article'
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• 2、在app下面创建一个forms.py的文件

• 3、在forms.py文件中使用模型表单

  from django import forms
  from . import models
  
  
  class ArticleForms(forms.ModelForm):
      """
      文章的form模型
      """
  
      class Meta(object):
          model = models.ArticleModel
          fields = '__all__'
  复制代码

• 4、视图中使用

  from django.shortcuts import render
  from django.views import View
  from django.http import HttpResponse
  from . import forms
  from . import models
  
  
  class ArticleView(View):
      """
      文章视图
      """
  
      def get(self, request, *args, **kwargs):
          form = forms.ArticleForms()
          return render(request, 'article.html', context={'form': form})
  
      def post(self, request, *args, **kwargs):
          form = forms.ArticleForms(request.POST)
          if form.is_valid():
              print('表单校验成功')
              title = form.cleaned_data.get('title')
              content = form.cleaned_data.get('content')
              author = form.cleaned_data.get('author')
              category = form.cleaned_data.get('category')
              print(title, content, author, category)
              return HttpResponse('成功')
          else:
              print('表单校验失败')
              print(form.get_errors())
              return HttpResponse('失败')
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• 5、前端html页面

  <form action="/book/" method="post">
      {% csrf_token %}
      <table>
          {{ form.as_table }}
          <tr>
              <td></td>
              <td>
                  <input type="submit" value="提交">
              </td>
          </tr>
      </table>
  </form>
  复制代码

二、关于模型表单别的知识点的补充

• 1、如果要使用全部的字段就在fields中使用__all__

  class ArticleForms(forms.ModelForm):
      """
      文章的form模型
      """
  
      class Meta(object):
          model = models.ArticleModel
          fields = '__all__'
  复制代码

• 2、如果是需要显示某些字段的时候

  class ArticleForms(forms.ModelForm):
      """
      文章的form模型
      """
  
      class Meta(object):
          model = models.ArticleModel
          fields = ['title', 'content']
  复制代码

• 3、如果模型中字段比较多使用排除的方法

  class ArticleForms(forms.ModelForm):
      """
      文章的form模型
      """
  
      class Meta(object):
          model = models.ArticleModel
          # fields = ['title', 'content']
          exclude = ['title']
  复制代码

三、关于错误信息的处理

之前是写在每一个字段上,现在没字段可写了

• 1、直接在forms.py中定义

  class ArticleForms(forms.ModelForm):
      """
      文章的form模型
      """
  
      class Meta(object)
  
  
      
  :
          model = models.ArticleModel
          fields = '__all__'
  
          error_messages = {
              'title': {
                  'max_length': 'title字段不能超过10字符',
                  'required': '请输入标题',
                  'invalid': '请输入一个有效的标题'
              }
          }
  复制代码

• 2、可以在models中给某一个字段添加

  from django.core import validators
  class ArticleModel(models.Model):
      """
      定义文章的数据模型
      """
      title = models.CharField(max_length=10, validators=[validators.MinValueValidator(limit_value=3)], verbose_name='标题')   
  复制代码

• 3、在forms.py中定义一个方法

  class ArticleForms(forms.ModelForm):
      """
      文章的form模型
      """
  
      class Meta(object):
          model = models.ArticleModel
          fields = '__all__'
          
      def clean_price(self):
          """
          自定义价格的校验
          :return: 
          """
          price = self.cleaned_data.get('price')
          if price < 0:
              raise forms.ValidationError('价格不能不能小于0元')
          return price
  复制代码

四、关于表单中save的方法

• 1、直接使用save保存数据

  class ArticleView(View):
      """
      文章视图
      """
  
      def get(self, request, *args, **kwargs):
          form = forms.ArticleForms()
          return render(request, 'article.html', context={'form': form})
  
      def post(self, request, *args, **kwargs):
          form = forms.ArticleForms(request.POST)
          if form.is_valid():
              print('表单校验成功')
              form.save()
              return HttpResponse('成功')
          else:
              print('表单校验失败')
              print(form.get_errors())
              return HttpResponse('失败')
  复制代码

• 2、当遇到模型中字段与表单中字段不一致的时候

  # 模型字段
  class UserModel(models.Model):
      username = models.CharField(max_length=100, verbose_name='用户名')
      password = models.CharField(max_length=100, verbose_name='密码')
  
      class Meta(object):
          db_table = 'c_user'
  复制代码

  # 表单校验的
  class RegisterForm(forms.ModelForm):
      pwd1 = forms.CharField(max_length=100, min_length=2)
      pwd2 = forms.CharField(max_length=100, min_length=2)
  
      def clean(self):
          cleaned_data = super().clean()
          pwd1 = cleaned_data.get('pwd1')
          pwd2 = cleaned_data.get('pwd2')
  
          if pwd1 !=pwd2:
              raise forms.ValidationError('两次密码不一致')
          return cleaned_data
  
      class Meta(object):
          model = models.UserModel
          exclude = ['password']
  复制代码

  # 视图中使用
  class RegisterView(View):
      """
      用户注册
      """
  
      def get(self, request, *args, **kwargs):
          form = forms.RegisterForm()
          return render(request, 'register.html', context={'form': form})
  
      def post(self, request, *args, **kwargs):
          form = forms.RegisterForm(request.POST)
          if form.is_valid():
              user = form.save(commit=False)
              user.password = form.cleaned_data.get('pwd1')
              user.save()
              return HttpResponse('成功')
          else:
              print(form.get_errors())
              return HttpResponse('失败')
  复制代码