Question

我有一个django项目，在项目中我有一个django forms.py，它包含一个字段调用类别，它选择由于对数据库进行查询而生成的框输入元素。如果我从数据库的选择下拉列表中选择一个选项，我会一直收到错误：

**strong text**Select a valid choice. That choice is not one of the available choices

以下是代码：

Forms.py

from django import forms
#from django.contrib.auth.models import User
from signer.models import CreateSingleSigner

class CreateSingleSignerForm(forms.ModelForm):
    category = forms.ModelChoiceField(
        required = True,
        help_text = 'category', 
        queryset=CreateSingleSigner.objects.all().values_list(
                'category', flat=True
            ).distinct()
    )

我的观点。

from django.shortcuts import render
from django.http import HttpResponse, HttpResponseRedirect
from signer.models import CreateSingleSigner
from signer.forms import CreateSingleSignerForm
from django.template import RequestContext

def singlesigner(request):
    context = {}
    if request.method == 'POST':
        createsinglesigner_form = CreateSingleSignerForm(data=request.POST)
        if createsinglesigner_form.is_valid():  
            createsinglesigner.category = request.POST['category']
            createsinglesigner_form.save()
        else:
            print createsinglesigner_form.errors
    else:
        # context['createsinglesigner'] = CreateSingleSigner()
        createsinglesigner_form =CreateSingleSignerForm()

    return render(request, "signer/singlesigner.html", {"createsinglesigner_form":createsinglesigner_form}, RequestContext(request))

my models.py

from django.db import models

class CreateSingleSigner(models.Model):
        category = models.CharField(max_length = 32)

有人可以告诉我哪里出错了吗？

Answer 1

尝试以下方法之一解决问题：

尝试在CreateSingleSigner模型中定义unicode的转换：

class CreateSingleSignerForm(forms.Form):

    def __unicode__(self):
        return self. category

<强>说明： ModelChoiceField将使用指定字段的__unicode__表示来显示和验证您的字段。

尝试在表单的__init__方法中设置选项

class CreateSingleSignerForm(forms.Form):
    category = forms.ChoiceField(choices=[], required=False)

    def __init__(self, *args, **kwargs):
        super(CreateSingleSignerForm, self).__init__(*args, **kwargs)
        self.fields['category'].choices = CreateSingleSigner.objects.all().values_list('category', flat=True).distinct()

说明 ModelChoiceField的查询集参数不能是values_list，因为它会保存关系，所以django必须使用完整的模型对象，而不是模型对象的某些值。

Django表示不选择选项

1 个答案: