Question

嘿，我正在尝试使用modelchoicefield在html中获取下拉列表。但是提交表单会产生无效的表单。我的代码如下。 views.py

class SubjectSelectFormView(View):
form_class = SubjectSelectForm
template_name = 'study/select_subject.html'

def get(self, request):
    form = self.form_class(user=request.user)
    return render(request, self.template_name, {'form':form})


def post(self, request):
    form = self.form_class(request.POST)
    if form.is_valid():
        subject = models.Subject.objects.get(name=form['name'])
        return HttpResponseRedirect('study:quiz', subject.subject_id)
    else:
        return HttpResponse('<h1>Failed</h1>')

forms.py

class SubjectSelectForm(forms.Form):

name = forms.ModelChoiceField(queryset=Subject.objects.all().order_by('name'), widget=forms.Select())

def __init__(self, *args, **kwargs):

    user = kwargs.pop('user', None)
    super(SubjectSelectForm,self).__init__(*args, **kwargs)
    self.fields['name'].queryset = Subject.objects.filter(user_id=user)

html

{% extends 'basic_home_app/base.html' %}
{% block content %}

<br>
<form class="form-horizontal" action="" method="post" enctype="multipart/form-data">
    {% csrf_token %}

    {{ form.as_p }}

    <input type="submit" value="Start">
</form>

{% endblock %}

Answer 1

首先，当发现张贴的表单无效时，应始终使用绑定的表单呈现相同的模板，这样您可以向用户显示错误：

def post(self, request):
    form = ...
    if form.is_valid():
        ...
    else:
        return render(request, self.template_name, {'form':form})

在模板内部，您可以使用以下任一显示错误：

{{ form.errors }}  # all form errors
{{ form.non_field_errors }}  # form errors that aren't for one specific field, use this if you're displaying the field errors separately

或

{{ form.name.errors }}  # just the errors for one specific field

第二，我假设您要以与通过get()请求向用户首次显示（空）时相同的方式初始化表单。

def post(self, request):
    form = self.form_class(request.POST, user=request.user)  # note the user

否则，您的form.__init__()方法将仅将Subject为user_id的{{1}}个对象设置为查询集。

Django下拉表单提交无效

1 个答案: