Django表单验证错误 - TypeError 'str'对象不可调用

Question

所以……我在这个问题上纠结了一段时间。当我尝试验证一个表单时，遇到了一个非常奇怪的错误。我传入一些输入数据，想测试当表单验证失败时的表现，也就是说，我预期它会验证失败。

这是我写的表单代码：

class CTAForm(forms.Form):      
    first_name = forms.CharField(max_length=50)
    email = forms.EmailField()
    phone = forms.CharField(max_length=15, required=False, label='Phone (optional)')

然后我在某个视图中调用这个代码来处理表单数据。

if cta_form.is_valid():

结果我得到了：

Exception Type:     TypeError
Exception Value:    'str' object is not callable
Exception Location:     /usr/lib/pymodules/python2.6/django/forms/forms.py in full_clean, line 246

错误追踪信息显示如下：

/usr/lib/pymodules/python2.6/django/forms/forms.py 在 full_clean:

1. except ValidationError, e:
2. self._errors[name] = self.error_class(e.messages) ...

▼ 本地变量
变量 值
e: ValidationError()
field: django.forms.fields.EmailField 对象在 <0x225c4d0c>
name: 'email'
self: blah.views.CTAForm 对象在 <0x2245b42c>
value: u' '

我感觉自己挺笨的。有没有人能给我一些关于这个问题的指导？谢谢。

---

编辑：根据要求，提供了更完整的视图代码

def cta_add(request):
    context_dict = {'categories': Category.objects.all().order_by('order'),}
    # we always expect to receive data via post
    if request.method =='POST':
        # get the current vid based on the parameter        
        current_vid = Video.objects.get(slug=request.POST['current_vid'])           
        # use this video to create our dynamic form so we get the valid cta values based on that video
        cta_form_class = make_cta_form(current_vid.cta_set.all().order_by('order'))
        # instantiate our new dynamic form based on the post data
        cta_form = cta_form_class(request.POST,  error_class='error')

        # if we got this far, we were able to generate a form to validate the user's input against.
        # If form validates, than process and take user to success screen           
        if cta_form.is_valid():

下面是辅助函数 make_cta_form

def make_cta_form(cta_set):
    cta_list =[]
    if not cta_set is None:
        for cta in cta_set:
            cta_list.append((cta.text, cta.text))

    class CTAForm(forms.Form):
        cta = forms.MultipleChoiceField(widget=forms.CheckboxSelectMultiple, choices=cta_list, label='', required=False)
        first_name = forms.CharField(max_length=50)
        email = forms.EmailField()
        phone = forms.CharField(max_length=15, required=False, label='Phone (optional)')        

    return CTAForm

Answer 1

在你的 views.py 文件里。当用户填写完表单后，你是这样做的吗？

from your_app.forms import *

def process_form(request):
    cta_form = CTAForm(request.POST)

    if cta_form.is_valid():
        # your code.

你需要把表单的 POST 数据作为构造函数的初始值传进去。

Answer 2

你遇到了一个错误，提示说字符串不能被调用，但你给表单设置的错误类是一个字符串，而不是一个错误类。

    cta_form = cta_form_class(request.POST,  error_class='error')

在文档中，我找到的关于error_class的唯一参考是一个字符串列表，所以你可以试试

    cta_form = cta_form_class(request.POST,  error_class=['error'])

不过，似乎更合理的做法是这样

    import forms 
    [...]
    cta_form = cta_form_class(request.POST,  error_class=forms.ValidationError("error"))

或者可能是：

    cta_form = cta_form_class(request.POST,  error_class=forms.ValidationError)