“用户”对象没有属性“验证错误”答案

【问题标题】：'User' object has no attribute 'ValidationError'“用户”对象没有属性“验证错误”
【发布时间】：2018-09-18 10:53:12
【问题描述】：

我正在尝试创建一个注册表单。一切正常，直到我尝试引发验证错误以防电子邮件已经存在。它说，'User' object has no attribute 'ValidationError'

这就是我所做的，

def register(request):
    if request.method == 'POST':
        form = RegistrationForm(request.POST)
        if form.is_valid():
            new_form = form.save(commit=False)
            mail = form.cleaned_data['email']
            if User.objects.filter(email=mail).exists():
                raise new_form.ValidationError('Looks like email already exists')
            else:
                new_form.save()
            username = request.POST.get('username')
            password = request.POST.get('password1')
            user = authenticate(username=username, password=password)
            login(request, user)
            return redirect(reverse('accounts:profile'))
    else:
        form = RegistrationForm()

我们如何解决这个问题？

【问题讨论】：

你可以在views.py和forms.py中发布你的导入
@VipinMohan 先生，我将其导入为from django.core.exceptions import ValidationError。此外，如果我从 View 中删除此 ValidationError 行，一切都会开始正常工作！
尝试导入 forms.ValidationError，而不是 core.exceptions.ValidationError

标签： python django django-forms

【解决方案1】：

验证表单错误时，应该从 django.forms 导入 validationError 而不是 django.core.exceptions

试试：

from django.forms import ValidationError

【讨论】：

请粘贴完整代码。 Models.py、forms.py 和 views.py

【解决方案2】：

尝试将以下方法添加到您的表单中

from django import forms
from .models import User

class RegistrationForm(forms.Form):

   # ..............
   # ..............

   def clean(self):
      mail = form.cleaned_data['email']
      if User.objects.filter(email=mail).exists():
          raise forms.ValidationError('Looks like email already exists')
      return self.cleaned_data

更改views.py中的代码

if User.objects.filter(email=mail).exists():
            raise new_form.ValidationError('Looks like email already exists')
        else:
            new_form.save()

到

new_form.save()

【讨论】：

先生，它再次引发了类似的错误，'RegistrationForm' object has no attribute 'ValidationError'
先生，现在出现错误'User' object has no attribute 'ValidationError'
我该怎么办？

【解决方案3】：

你应该像这样引发 ValidationError：

raise ValidationError('Looks like email already exists')

这里是完整的代码：

def register(request):
    if request.method == 'POST':
        form = RegistrationForm(request.POST)
            if form.is_valid():
                new_form = form.save(commit=False)
                mail = form.cleaned_data['email']
            if User.objects.filter(email=mail).exists():
                raise ValidationError('Looks like email already exists')
            else:
                new_form.save()
            username = request.POST.get('username')
            password = request.POST.get('password1')
            user = authenticate(username=username, password=password)
            login(request, user)
            return redirect(reverse('accounts:profile'))
    else:
        form = RegistrationForm()

【讨论】：

【解决方案4】：

if User.objects.filter(email=mail).exists():
            raise new_form.ValidationError('Looks like email already exists')

使用“forms”而不是“new_form”，结果应该是这样的

if User.objects.filter(email=mail).exists():
                raise forms.ValidationError('Looks like email already exists')

【讨论】：

【解决方案5】：

我输入如下，它在 django-2.0.7 上工作：

from django import forms
from django.contrib.auth import login
from django.contrib.auth.models import User
from django.shortcuts import render, redirect


class RegistrationForm(forms.ModelForm):
    def clean_email(self):
        email = self.cleaned_data['email']
        if self.Meta.model.objects.filter(email=email).exists():
            raise forms.ValidationError('Looks like email already exists')
        return email

    class Meta:
        model = User
        fields = ('username', 'password', 'email')


def register(request):
    if request.method == 'POST':
        form = RegistrationForm(request.POST)
        if form.is_valid():
            user = form.save(commit=False)
            user.set_password(user.password)
            user.save()
            login(request, user)
            return redirect('accounts:profile')
    else:
        form = RegistrationForm()
    return render(request, 'register.html', {'form': form})

【讨论】：