匹配查詢不存在

Question

我試圖捕捉異常，但不work.This在我看來代碼：

@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/') 

我還與試圖：「除了act_edit.DoesNotExist：」 但錯誤仍然存​​在「活動匹配查詢不存在」。 有什麼想法？

謝謝！

Answer 1

您需要移動可能導致try:子句正文中的異常的語句。

的語法是 「嘗試：東西抓東西：」 你東西是try:

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

上面應該是

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

Answer 2

你有冗餘的一點點捕捉異常意味着您不必檢查act_edit是否爲空，因爲如果它爲空，它將引發DoesNotExist。此外，該模型有DoesNotExist不是實例。

@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/')