Question

我有一个模型，用户有ManyToManyField，我希望在他/她在Choice模型中提交表单时记录登录用户，但此代码阻止我这样做。我使用login_required装饰器强制用户先登录（这就是我想要的）。

models.py：

from django.db import models
from django.contrib.auth.models import User

QUESTION_CHOICES = (
        ("choice_1", "Choice 1"),
        ("choice_2", "Choice 2"),
        ("choice_3", "Choice 3"),
    )


class Choice(models.Model):
    users   = models.ManyToManyField(User)
    choices = models.CharField(max_length=256, choices=QUESTION_CHOICES, unique=True)
    vote    = models.IntegerField(default=0)

    def __str__(self):
        return self.choices + " " + "-" + " " + str(self.vote)

views.py：

from django.shortcuts import render
from django.contrib.auth.decorators import login_required

from .models import Choice

@login_required
def index(request):
    food = request.POST.get('sunday')
    user_v = None
    get_choices = Choice.objects.values('choices', 'vote')

    new_choices = list(get_choices)

    for q in new_choices:
        choice = q['choices']
        vote_v   = q['vote']

        if food:
            if food == choice:
                if request.user.is_authenticated():
                    user_v = request.user
                    print(user_v)               # it prints out correctly after sucessful form submit
                vote_v += 1
                model_conn = Choice.objects.get(choices=choice)
                model_conn.vote = vote_v
                model_conn.users = user_v       # this is where I get an error
                model_conn.save()

    return render(request, 'index.html', {})

Answer 1

您正在为用户使用ManyToMany字段，因此需要使用add方法将当前用户添加到用户列表中：

model_conn.users.add(user_v)

如果您需要先清除相关用户列表，可以使用clear：

model_conn.users.clear()
model_conn.users.add(user_v)

'用户'对象在Django 1.11.8中不可迭代

1 个答案: