“在賦值 django 之前引用的局部變量 'form_b'”

Question

def register(request):
    if not request.user.is_authenticated:
        if request.POST.get('submit') == 'sign_up':
            form = RegisterForm(request.POST)
            if form.is_valid():
                form.save()
            form = RegisterForm()
        elif request.POST.get('submit') == 'log_in':
            form1 = LogInForm(request=request, data=request.POST)
            if form1.is_valid():
                uname = form1.cleaned_data['username']
                upass = form1.cleaned_data['password']
                user = authenticate(username=uname, password=upass)
                if user is not None:
                    login(request, user)
                    return redirect('/')
        else:
            form_b = LogInForm()
            form = RegisterForm()
        return render(request, 'auth.html', {'form': form, 'form1': form_b})

以上是我的看法 function

<form class="loginForm" action="" method="POST" novalidate>
    {% csrf_token %} 
    {% for field in form %}
       <p> {{field.label_tag}}  {{field}} </p>
    {% endfor %}
    <button type="submit" class="btnLogin" name='submit' value='sign_up'>Sing Up</button>
 </form>
 <form class="loginForm" action="" method="post" novalidate>
    {% csrf_token %}
    {% for field in form1 %}
       <p> {{field.label_tag}}  {{field}} </p>
    {% endfor %}
 <button  class="btnLogin" type="submit"  name='submit' value='log_in'>Log In </button>
 </form>

在視圖中呈現兩個 forms function 代碼工作正常，但是當我點擊注冊時出現此錯誤，顯示“在賦值 django 之前引用了局部變量 'form_b'”

Answer 1

如果最終使用它，則需要在每種可能的情況下分配此變量，或者只需為其存在的部分添加獨占返回。 在您的特殊情況下，我建議將form_b更改為form1並將它們移到if not request.user.is_authenticated條件的前面：

def register(request):
    if not request.user.is_authenticated:
        form1 = LogInForm()
        form = RegisterForm()
        if request.POST.get('submit') == 'sign_up':
            ...
        elif request.POST.get('submit') == 'log_in':
            ...
        return render(request, 'auth.html', {'form': form, 'form1': form1})

這樣，您將確保它們兩者都存在。 如果另一個條件是True ，那么它將覆蓋空表單的創建。