modelform 使用

modelForm
 
(1)
model的知识点：
 
class UserInfo(AbstractUser):
    tel = models.CharField(max_length=32)
    gender = models.IntegerField(choices=((1, "男"), (2, "女")), default=1)
 
yuan = UserInfo.objects.get(pk=1)
yuan.get_gender_display()
 
(2)
modelform使用
model.py:
 
class Book(models.Model):
    nid = models.AutoField(primary_key=True)
    title = models.CharField(max_length=32)
    price = models.DecimalField(max_digits=8, decimal_places=2)  # 999999.99
    pub_date = models.DateTimeField()  # "2012-12-12"
 
    # comment_count=models.IntegerField(default=100)
    # poll_count=models.IntegerField(default=100)
 
    publish = models.ForeignKey(to="Publish", on_delete=models.CASCADE)  # 级联删除
    authors = models.ManyToManyField(to="Author")
 
    def __str__(self):
        return self.title
 
form.py:
 
# 构建modelform
class BookModelForm(forms.ModelForm):
    class Meta:
        model = Book
        fields = "__all__"
 
'''
BookModelForm等同于：
     class BookForm(forms.Form):
             title=forms.CharField(max_length=32)
             price=forms.IntegerField()
             pub_date=forms.DateField(widget=widgets.TextInput(attrs={"type":"date"}))
             #publish=forms.ChoiceField(choices=[(1,"AAA"),(2,"BBB")])
             publish=forms.ModelChoiceField(queryset=Publish.objects.all())
             authors=forms.ModelMultipleChoiceField(queryset=Author.objects.all())
 
'''
 
逻辑：
添加书籍：
 
def add(reqeust):
    if GET请求：
    form = BookModelForm()
    return render(reqeust, {"form": form})
    '''
    渲染页面
        <form action="" method="post" novalidate>
              {% csrf_token %}
                {% for field in form %}
                      <div class="form-group">
                           <label for="title">{{ field.label }}</label>
                           {{ field }}
                           <span>{{ field.errors.0 }}</span>
                      </div>
               {% endfor %}
              <input type="submit" value="提交" class="btn btn-default pull-right">
        </form>
    '''
 
else POST请求：
form = BookModelForm(request.POST)
if form.is_valid():
    form.save()  # Book.objects.create(clean_data)
    return redirect("/")
else:
    return render(reqeust, {"form": form})
 
编辑书籍：
 
def edit(request, id):
    edit_obj = Book.objects.get(pk=id)
    if GET请求：
    form = BookModelForm(instance=edit_obj)
    return render(reqeust, {"form": form})
    '''
    渲染页面同添加页面
 
    '''
 
else POST请求：
form = BookModelForm(request.POST, instance=edit_obj)
if form.is_valid():
    form.save()  # edit_obj.update(clean_data)
    return redirect("/")
else:
    return render(reqeust, {"form": form})