UnboundLocalError：分配前已引用局部变量“ form”

Question

I want to create a new project creation page, the goal is that the user can validate his form, I have an error in the code below

This is the message error :

local variable 'form' referenced before assignment

Request Method:     GET
Request URL:    http://127.0.0.1:8000/dash/create/
Django Version:     2.1.4
Exception Type:     UnboundLocalError
Exception Value:    

local variable 'form' referenced before assignment

Answer 1

并非所有路径都定义表单实例（例如，用户使用GET查看页面），要修复此问题，只需将表单初始化为None或if语句之前的内容

Answer 2

Corrected for visibility.

@login_required
def createproject(request):
    form = None # added line
    if request.method == 'POST':
        form = forms.CreateProject(request.POST)
        if form.is_valid():
            return redirect('dashboard:dashboard-createproject')
        else:
            form = forms.CreateProject
    return render(request, 'dashboard/createproject.html', {'form': form})