Django 表单 is_valid() 失败 [英] Django form is_valid() fails

问题描述

我是网络开发的真正初学者.以下代码在 is_valid() 检查中失败.但我不明白为什么:表单是否应该从 POST 数据中获取其数据?

I am a real beginner in web development. The following code is failing at the is_valid() check. But I do not understand why: The form should get its data filled from the POST-data or not?

型号:

class Statement(models.Model):
    text = models.CharField(max_length=255)
    user = models.ForeignKey(User)
    time = models.DateField()
    views = models.IntegerField()

模型形式:

class StatementForm(ModelForm):
    class Meta: 
        model = Statement
        widgets = {
                   'time':forms.HiddenInput(),
                   'user':forms.HiddenInput(), 
                   'views':forms.HiddenInput(), 
        }

查看功能:

def new(request):  
    if request.method == 'POST': # If the form has been submitted...
        form = StatementForm(request.POST) # A form bound to the POST data
        if form.is_valid():
            stmt = form.save()
            path = 'stmt/' + stmt.id
            return render_to_response(path, {'stmt': stmt})
    else:  
        c = {}
        c.update(csrf(request))
        loggedin_user = request.user 
        d = datetime.now()
        form = StatementForm(request.POST, initial={'time': d.strftime("%Y-%m-%d %H:%M:%S"), 'user':loggedin_user, 'views':0})
        return render_to_response('new_stmt.html', {'form': form, },context_instance=RequestContext(request))

我找到了类似的主题并尝试了很多.这就是我认为它应该工作的方式.我真的需要建议.

I found similar topics and tried a lot. This is how i think it should work. I really need advice.

推荐答案

您的模型的所有字段都是必需的.因此，form.is_valid() 将是 True，如果所有字段都填充了正确的值并且没有空白.您已将字段 time、user、views 声明为隐藏字段.您确定已将它们填写在模板表单中吗?此外，您可能希望自动标记字段 time = models.DateField().修改您的模型字段，如

All fields of your model are required. So, form.is_valid() will be True, if all fields are filled with correct values and are not blanked. You have declared fields time, user, views as hidden fields. Are you sure, that you have filled them in your template form? Also, you may want to auto stamp field time = models.DateField(). Modify your model field like

time = models.DateField(auto_now=True)`. 

此后您就不必在模板表单中自己填写了.

After this you don't have to fill it by yourself in template form.

您的视图在所有情况下都必须返回 HttpResponse 对象.如果您的表单无效，即如果 form.is_valid() 将返回 False，那么您的视图将不会返回 HttpResponse 对象.这可能是你失败的根源.为if form.is_valid()添加else语句:

Your view must return HttpResponse object in all cases. If your form is not valid, i.e. if form.is_valid() will return False, then no HttpResponse object will be returned by your view. This can be the source of your fail. Add else statement for if form.is_valid():

from django.http import Http404
def new(request):  
    if request.method == 'POST': # If the form has been submitted...
        form = StatementForm(request.POST) # A form bound to the POST data
        if form.is_valid():
            stmt = form.save()
            path = 'stmt/' + stmt.id
            return render_to_response(path, {'stmt': stmt})
        else:
            # Do something in case if form is not valid
            raise Http404 
    else: 
        # Your code without changes

这篇关于Django 表单 is_valid() 失败的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！