带有可能不存在的元素的 Django 进程形式

Question

我有一个表单，其中包含一个未绑定到模型的元素。在某些情况下，此表单元素根本不会在 HTML 中呈现，但是当我发布表单时，我希望它仍然存在，如果它不存在，它仍然会进行验证。

我已经研究了更改发布到某物的值的可能性，但看不到执行此操作的方法。我已经尝试覆盖干净的方法，但我不确定您是如何做到的。我尝试将其设置为 required=False，但这没有效果，因为它似乎至少需要发布一个空值。

我的表单类如下所示：

class StimForm(ModelForm):
    body = forms.CharField( widget=forms.Textarea )
    userstims = forms.ChoiceField(required=False)
    class Meta:
        model = Stim
        fields = ['body','privacytype','stimtype']

HTML 如下。由于这可能是隐藏的，因此在某些情况下不会发布用户的数据。我仍然希望表单验证在这些情况下起作用。

  <div class='form-group row' id="userstim" style="display:none;">
      <label class="col-2 col-form-label">Add Custom Stim:</label>
      <div class="col-5">
        {{ form.userstims }}
      </div>
      <div class="col-5">
        <a href="/stimbook/adduserstim">Add Stim</a>
      </div>
  </div>

更新 - 视图：

def stimboard(request):
    user = getuser(request)
    if user == None:
        #redirect
        return HttpResponseRedirect('/user/login')
    #Get the user defined stims if they exist
    try:
        userstims = UserStim.objects.filter(user=user)
    except:
        userstims = []
    #Get the id of the user to look up
    stimuser = User.objects.get(id=request.GET.get("id"))
    #Get the user profile data
    profiledata = getprofiledata(stimuser)
    #forms
    commentform = StimCommentForm()
    if request.POST:
        form = StimForm(request.POST,mystims=userstims)
        userstimform = UserStimForm(request.POST)
        if form.is_valid():
            #Create stim
            print("Creating Stim")
            if form.cleaned_data['stimtype'] == "OT":
                #Create custom stim
                Stim.objects.create(
                    body = form.cleaned_data['body'],
                    poster = user,
                    board = stimuser,
                    privacytype = form.cleaned_data['privacytype'],
                    stimtype = form.cleaned_data['stimtype'],
                    otherstim = UserStim.objects.get(id=form.cleaned_data['userstims'])
                )
            else:
                Stim.objects.create(
                    body = form.cleaned_data['body'],
                    poster = user,
                    board = stimuser,
                    privacytype = form.cleaned_data['privacytype'],
                    stimtype = form.cleaned_data['stimtype']
                )
    else:
        form = StimForm(request.POST,mystims=userstims)
        userstimform = UserStimForm()
    #Get friendship status of user
    buddystatus = Buddy.buddies.buddystatus(user,stimuser)
    #Get public stims from user
    stims = Stim.objects.filter(board=stimuser,privacytype="PU")
    #Check if buddy and get private stims then add them to the stims
    isbuddy = Buddy.buddies.isbuddy(user,stimuser)
    if isbuddy:
        privatestims = Stim.objects.filter(board=stimuser,privacytype="PR")
        stims = stims | privatestims
    stimlist = []
    #get the comments for each stim
    for stim in stims:
        stimdict = dict()
        stimdict['id'] = stim.id
        stimdict['poster'] = stim.poster
        stimdict['body'] = stim.body
        stimdict['dateofpost'] = stim.dateofpost
        stimdict['privacytype'] = stim.privacytype
        if stim.stimtype == "OT":
            #get the custom stim
            stimdict['stimtype'] = stim.otherstim.stimname
        else:
            print(type(stim.stimtype))
            stimdict['stimtype'] = getstimtype(stim.stimtype)
        stimdict['stimcomments'] = StimComment.objects.filter(stim=stim)
        stimlist.append(stimdict)
    stimlist.sort(key=lambda x: x['dateofpost'], reverse=True)
    return render(request, 'stimboard/stimboard.html', { 'stimuser' : stimuser, 'stims' : stimlist, 'buddystatus' : buddystatus,
                                                        'commentform' : commentform, 'form' : form, 'userstimform' : userstimform,
                                                         'isbuddy' : isbuddy, 'profiledata' : profiledata })

更新 - 初始化方法

def __init__(self, *args, **kwargs):
        mystimsqs = kwargs.pop('mystims')
        super(StimForm, self).__init__(*args, **kwargs)
        print("kwargs")
        mystims = []
        for stim in mystimsqs:
            stimlist = (stim.id,stim.stimname)
            mystims.append(stimlist)
        self.fields['userstims'] = forms.ChoiceField(
            choices=tuple(mystims)
        )

Answer 1

在__init__方法中，您将完全重新定义userstims字段，并用未设置required=False的新字段覆盖它。您应该在重定义中传入该选项，或者最好避免重新定义整个字段，而直接设置选项：

self.fields['userstims'].choices = mystims

另请注意，您的循环最好写成列表理解：

mystims = [(stim.id,stim.stimname) for stim in mystimqs]