django - 总结 - ModelForm

 gender = forms.ChoiceField(choices=((1, '男'), (2, '女'), (3, '其他')))  # 与sql没关系
 publish = forms.ChoiceField(choices=Publish.objects.all().values_list('pk', 'name'))
 publish = forms.ModelChoiceField(queryset=Publish.objects.all(), label='出版社')
 authors = forms.ModelMultipleChoiceField(queryset=Author.objects.all(), label='作者')

-------->forms在post提交数据时,可以验证并将数据返回前端,

　　　　　　get请求时,如何将数据返回前端？

ModelForm

 from django.forms import ModelForm
 from django.forms import widgets as wid  # 因为重名，所以起个别名！
 class BookForm(ModelForm):
     class Meta:
         model = Book  # 关联的哪个模型
         fields = "__all__"  # 对所有字段转换　 ["title",...]
         exclude = None  # 排除的字段

         # 自定义在前端显示的名字
         labels = {"title": "书籍名称", "price": "价格", "date": "日期", "publish": "出版社", "authors": "作者"}
         widgets = {
             'title': wid.TextInput(attrs={'class': 'form-control'}),
             'price': wid.TextInput(attrs={'class': 'form-control'}),
             'date': wid.TextInput(attrs={'class': 'form-control', 'type': 'date'}),
             'publish': wid.Select(attrs={'class': 'form-control'}),
             'authors': wid.SelectMultiple(attrs={'class': 'form-control'})
         }
         error_messages = {
             'title': {'required': '不能为空'},
             'price': {'required': '不能为空'},
             'date': {'required': '不能为空', 'invalid': '格式错误'},
             'publish': {'required': '不能为空'},
             'authors': {'required': '不能为空'},
         }

 #  editdisplay
 edit_book = Book.objects.filter(pk=edit_book_id).first()
 # form = BookForm(initial={"title": edit_book.title, "price": edit_book.price, "date": edit_book.date,
 #                          "publish": edit_book.publish, 'authors': edit_book.authors.all()})
 form = BookForm(initial=edit_book)
 return render(request, "edit.html", locals())

 # create、update
 form = BookForm(request.POST)  # create
 if form.is_valid():
      form.save()  # form.model.objects.create(request.POST)      

 form = BookForm(request.POST,instance=edit_book)  # update
 if form.is_valid():
      form.save()   # edit_book.update(request.POST)

 # display
 {% for book in book_list %}
        <tr>
            <td>{{ book.title }}</td>
            <td>{{ book.price }}</td>
            <td>{{ book.date|date:"Y-m-d" }}</td>
            <td>{{ book.publish.name }}</td>
            <td>{{ book.authors.all }}</td>
             <td><a href="/book/edit/{{book.pk}}"><button>编辑</button></a></td>
        </tr>
     {% endfor %}