匹配的查询不存在

Question

我正在尝试捕获异常，但无效。以下是我视图中的代码：

@login_required 
def activities_edit(request, edit):

    ActivityFormSet = modelformset_factory(Activity, can_delete=True)
    act_edit= Activity.objects.filter(campaing=1).get(pk=edit)
    try:
        if act_edit:
            if request.method == 'POST':
                formset = ActivityFormSet(request.POST, request.FILES, queryset=Activity.objects.filter(pk=edit))       
                if formset.is_valid():
                    formset.save()
                    return HttpResponseRedirect('/activities/')
            else:
                formset = ActivityFormSet(queryset=Activity.objects.filter(pk=edit))
    except act_edit.DoesNotExist:
        return HttpResponseRedirect('/activities/')

我还尝试了：“除了act_edit.DoesNotExist:”但错误仍然存在“活动匹配查询不存在”。你知道吗？

谢谢

Answer 1

您有一点冗余捕获异常意味着您不必检查act_edit是否为空，因为如果为空，它将引发DoesNotExist。此外，模型具有DoesNotExist而不是实例。

@login_required 
def activities_edit(request, edit):

    ActivityFormSet = modelformset_factory(Activity, can_delete=True)       
    try:
        act_edit= Activity.objects.filter(campaing=1).get(pk=edit)

        if request.method == 'POST':
            formset = ActivityFormSet(request.POST, request.FILES, queryset=Activity.objects.filter(pk=edit))       
            if formset.is_valid():
                formset.save()
                return HttpResponseRedirect('/activities/')
        else:
            formset = ActivityFormSet(queryset=Activity.objects.filter(pk=edit))
            #HttpResponse not returned error here.
    except Activity.DoesNotExist:
        return HttpResponseRedirect('/activities/')

Answer 2

您需要移动可能导致try:子句主体中出现异常的语句。

语法是try：某物捕获某物：你的某物位于try：之上

act_edit= Activity.objects.filter(campaing=1).get(pk=edit)
try:

应该是

try:
   act_edit = Activity.objects.filter(campaing=1).get(pk=edit)