Django：如何获取与列表相关的ForeignKey记录？

Question

I am using Django v1.11. Here are 2 models:

class Task(models.Model):
    title = models.CharField()

class TaskUser(models.Model):
    task = models.ForeignKey(Task, related_name='task_user')
    user = models.ForeignKey(settings.AUTH_USER_MODEL, related_name='+')

So, I want to get list of tasks and print in one column list of users that are related to this task. How to do that? The problem is tried a lot: select_related , prefetch_related('task_user') and so on.. but nothing works. In some cases there are no sql error, but it prints task.User.None

tasks = Task.objects.all()

View must be:

<table>
<tr>
    <td>Title</td>
    <td>Users</td>
</tr>
{% for task in tasks %}
<tr>
    <td>{{ task.title }}</td>
    <td>
    {% for user in task.users %}
        {{ user.id }}
    {% endfor %}
    </td>
</tr>
{% endfor %}
</table>

Answer 1

Add a many-to-many field to Task, using the through model you already have:

class Task(models.Model):
    users = models.ManyToManyField(settings.AUTH_USER_MODEL, through='TaskUser')

and use .all when iterating:

{% for user in task.users.all %}
    {{ user.id }}
{% endfor %}

(Note, you should remove the related_name='+' from the TaskUser.user field.)