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 modelsfrom django.core import validatorsclass 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'复制代码

• 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 formsfrom . import modelsclass 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 renderfrom django.views import Viewfrom django.http import HttpResponsefrom . import formsfrom . import modelsclass 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')复制代码

• 5、前端html页面

        
             {% csrf_token %}    
         
                  {
       { form.as_table }}        
        
  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 validatorsclass 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