django視圖沒有返回HttpResponse對象。它返回無不是

Question

這是我的觀點：

def GeneralUserPictureChange(request, pk, username): 
thumb = GeneralUser.objects.get(pk=pk) 
if thumb.username == request.user: 
    if request.method == 'POST': 
     form = GeneralUserPictureChangeForm(request.POST, request.FILES) 
     if form.is_valid(): 
      thumb.thumbnail = form.cleaned_data['thumbnail'] 
      thumb.save() 
      return redirect("user_profile", pk, username) 
     else: 
      return render_to_response("gnu_picture_change.html", {"form":form, "basic_info":thumb}, context_instance=RequestContext(request)) 
    else: 
     form = GeneralUserPictureChangeForm() 
    return render_to_response("gnu_picture_change.html", {"form":form, "basic_info":thumb}, context_instance=RequestContext(request)) 

當我做到這一點給出了錯誤didnt返回HttpResponse對象。但是，當我刪除行 if thumb.username == request.user:並繼續正確的縮進它不提供錯誤..

需要幫助...

Answer 1

你比較的username場和user對象在這裏：

if thumb.username == request.user: 

• thumb.username可能返回一個字符串像'JohnDoe'
• request.user返回一個對象，如：<User: johndoe>

所以if似乎是假ALLWAYS

爲了解決這個問題，你應該做的：

if thumb.username == request.user.username: 

• 如果第一個條件爲假，會發生什麼？你需要一個替代的回報，相同的縮進if thumb.username...

---

你得到的無而不是HttpResponse對象，因爲你不具備的情況下返回第一if是假

def GeneralUserPictureChange(request, pk, username): 
thumb = GeneralUser.objects.get(pk=pk) 
if thumb.username == request.user: 
    if request.method == 'POST': 
     form = GeneralUserPictureChangeForm(request.POST, request.FILES) 
     if form.is_valid(): 
      thumb.thumbnail = form.cleaned_data['thumbnail'] 
      thumb.save() 
      return redirect("user_profile", pk, username) 
     else: 
      return render_to_response("gnu_picture_change.html", {"form":form, "basic_info":thumb}, context_instance=RequestContext(request)) 
    else: 
     form = GeneralUserPictureChangeForm() 
    return render_to_response("gnu_picture_change.html", {"form":form, "basic_info":thumb}, context_instance=RequestContext(request)) 

# You need a return like this one, in case the first if is false 
return render_to_response("gnu_picture_change.html", {"Error":'Not valid username'}, context_instance=RequestContext(request))