对于is_valid()，没有错误的Django表单返回False

I'm generating a form from metadata

我正在从元数据生成表单

class MeasureForm(forms.Form):
    def __init__(self,*args,**kwargs):
        super(MeasureForm,self).__init__()
        measure_id = kwargs['measure_id']
        m = Measure.objects.get(pk=measure_id);
        if (m):
            # add the measure identifier as a hidden field
            self.fields["measure_id"] = forms.IntegerField(initial = m.id , widget=forms.HiddenInput())
            for mp in MeasureParameters.objects.filter(measure = m):
                # get the NVL'ed copy of the parameter
                p = mp.get_parameter_for_measure()
                if not p.is_modifiable:
                    # the file has a constant value
                    if (p.values and p.default): # constant must have both values and default index
                        value_ = p.values[p.values.keys()[p.default-1]];
                        self.fields[p.name] = forms.IntegerField(
                            label = p.description , 
                            initial = value_, 
                            help_text = p.help_text)
                        self.fields[p.name].widget.attrs['readonly'] = True
                    else:
                        raise Exception("Parameter set as unmodifiable but has no value. \
                                        [measure: %s, parameter: %s, measureparameter %s]"
                                        % (m.id , p.id , mp.__unicode__()))
                elif (p.values):
                    # convert hstore dict to list of tuples for the choices to read
                    values_ = [(v, k) for k, v in p.values.iteritems()];
                    # set default if exists , else take the first item
                    default_ = values_[p.default-1][0] if p.default else values_[0][0]
                    self.fields[p.name] = forms.ChoiceField(
                        label = p.description , 
                        choices = values_ , 
                        initial = default_, 
                        help_text = p.help_text)
                else:
                    self.fields[p.name] = forms.IntegerField(label = p.description, help_text = p.help_text)
                if (not p.is_visible):
                    self.fields[p.name].widget = forms.HiddenInput()
        else:
            raise Exception ("Could not find measure. [measure %s]" % (m.id))

    def clean(self):
        return self.cleaned_data;

this is my view

这是我的观点

def index(request,measure_id = None):

    owners = Owner.objects.all()    
    form = None
    result = None
    title = None;
    msg = None;

    # handle the form
    if request.method == 'POST': # the form has been submitted
        form = MeasureForm(request.POST, measure_id = request.POST.get('measure_id')) # A form bound to the POST data
        result = -100
        if form.is_valid(): # All validation rules pass
            result = 100
        msg = "%s" % repr(form.errors) # list of validation errors
    else:
        if (measure_id):
            title = Measure.objects.get(pk=measure_id).name;
            # make an unbound form
            form = MeasureForm(measure_id = measure_id)

    return render(request, 'calc/index.html' ,
            {'owners' : owners, 
             'form'   : form , 
             'title'  : title , 
             'result' : result, 
             'debug'  : msg })

this is a snippet from my template

这是我的模板中的一个片段。

<div class="content">
    {{ form.errors }}
    {{ form.non_field_errors }}
    {% if form %}
        <h2>{{ title }}</h2>
        <form action="/calc/{{m.id}}" method="post">{% csrf_token %}
            {{ form.as_p }}
        <input type="submit" value="Calculate" />
        </form>
    {% if result %}
        The Result is  <span class="result"> {{ result }} </span>
    {% endif %}
</div>

So i get empty braces {} for "%s" % repr(form.errors), form.errors and form.non_field_errors returns nothing. the form posts and I can see the raw data in the request but i keep getting false from is_valid(). why is that ?

因此，我将为“%s”% repr(form.errors)表单获取空大括号{}。错误和形式。non_field_errors回报什么。表单发布后，我可以在请求中看到原始数据，但is_valid()却不断出错。这是为什么呢?

EDIT: when checking if the form is bound i also get false. guessing this is the problem. why isn't the form bound after the call for form = MeasureForm(request.POST, measure_id = request.POST.get('measure_id')) ?

编辑:当检查窗体是否被绑定时，我也会得到false。这就是问题所在。为什么表单在呼唤表单之后不被约束?POST, measure_id = request.POST.get('measure_id') ?

** django newbie, Thanks.

* * django新手,谢谢。

1 个解决方案

#1

Because you're not passing the arguments into the super call. You should do this:

因为你没有把参数传递给super call。你应该这么做:

    super(MeasureForm,self).__init__(*args, **kwargs)

otherwise the form will never actually be initialised with the POST data.

否则，表单将永远不会使用POST数据进行初始化。

Edit after comment The answer to that question didn't recommend removing all the arguments from the super call. If you're passing in measure_id you'll simply need to remove it from kwargs beforehand:

编辑一个又一个的评论，这个问题的答案不建议从super call中删除所有的参数。如果你正在传入measure_id，你只需要事先将它从kwargs移除:

def __init__(self, *args, **kwargs):
    measure_id = kwargs.pop('measure_id', None)
    super(MeasureForm,self).__init__(*args, **kwargs)

#1