如何修复缺少 1 个必需的位置参数“请求”错误？

Question

/risk/riskset 处的类型错误 get_context_data() 缺少 1 个必需的位置参数：“请求”。

在此处查看代码： 模型.py

class RiskSet(models.Model):
    name = models.CharField('Risk set', max_length=500, blank=True, default = '')
    owner = models.ForeignKey(User, verbose_name = 'owner', on_delete=models.PROTECT, null=True)
    risk = models.ForeignKey(Risk, verbose_name = 'risk', on_delete=models.PROTECT, null = True)
    parent_risk_set = models.ForeignKey('self', related_name="child_risk_set", on_delete=models.PROTECT, blank=True, null=True)
  
    def __str__(self):
        return "{}".format(self.name)

forms.py

class RiskSetForm(forms.ModelForm):
    RiskID1 = forms.ModelMultipleChoiceField(queryset=Risk.objects.all(), required=True,
                                             widget=forms.SelectMultiple(attrs={'class': 'select2'}),
                                             label = 'Risk id')
                                                         
    def __init__(self, *args, **kwargs):
        super(RiskSetForm, self).__init__(*args, **kwargs)
        print(self)
        for visible in self.visible_fields():
            visible.field.widget.attrs['class'] = 'form-control'

    class Meta:
        model = RiskSet
        fields = ['name', 'owner', 'risk', 'parent_risk_set']

views.py

class RiskSet(FormView, SingleTableMixin):
    template_name = "risk/RiskSet.html"
    model = RiskSet
    form_class = RiskSetForm
    def get_context_data(self, request):
        form = RiskSetForm(request.POST or None)
        if form.is_valid():
            form.save()    
        # Call the base implementation first to get a context
        context = super().get_context_data(**kwargs)
        # Add in a QuerySet of all the books
        context['page'] = 'risk'
        return context

现在我得到了错误：

/risk/riskset 处的类型错误 get_context_data() 缺少 1 个必需的位置参数：'request'

请帮忙！

Answer 1

get_context_data 不 与request 参数一起工作。你可以传递任意数量的参数，但这里你的get_context_data 只会在被请求调用时运行。您使用self.request 访问请求：

class RiskSet(SingleTableMixin, FormView):
    template_name = "risk/RiskSet.html"
    model = RiskSet
    form_class = RiskSetForm
    
    def get_context_data(self, *args, **kwargs):
        form = RiskSetForm(self.request.POST or None)
        if form.is_valid():
            form.save()    
        # Call the base implementation first to get a context
        context = super().get_context_data(*args, **kwargs)
        # Add in a QuerySet of all the books
        context['page'] = 'risk'
        return context

此外，在get_context_data 方法中这样做是没有意义的。 FormView 有为此制定的例程。它您可能还可以使用CreateView，它将删除更多样板代码，例如：

from django.views.generic import CreateView

class RiskSet(SingleTableMixin, CreateView):
    template_name = "risk/RiskSet.html"
    model = RiskSet
    form_class = RiskSetForm
    success_url = 'path-to-url-when-form-is-valid'
    
    def get_context_data(self, *args, **kwargs):
        context = super().get_context_data(*args, **kwargs)
        # Add in a QuerySet of all the books
        context['page'] = 'risk'
        return context