如何反向查询ManytoMany Django

Question

我有这两个模型，我想在我的页面中显示带有特定任务的项目。这些是我的模型：

class Project (models.Model):
    name = models.CharField(verbose_name="Project name", max_length=25)
    tasks = models.ManyToManyField(Task, verbose_name="tasksInProject", blank=True,
                                   related_name="projects+")

class Task(models.Model):
    name = models.CharField(verbose_name="Task", max_length=50)

我称这个视图为：

class TaskToProjectFilterView(DetailView):
    model = Task
    template_name = "vivs/task_filter.html"
    context_object_name = "task_filter"

这是我的 html 模板：

<h4>filter : {{ task_filter }} </h4>
<h4>projects : 
{% for element in task_filter.projects.all %}
    {{ element }} 
{% endfor %}
</h4>

此代码显示 {{ task_filter }} 但不显示 {{ task_filter.projects.all }} 的列表。

你能帮帮我吗？我不明白我的错误。谢谢！

Answer 1

如 schwobaseggl 所述，删除 + 标志，它应该可以按预期工作，使用：

{% for element in task_filter.projects.all %}

来自Django Docs：

If you’d prefer Django not to create a backwards relation, set related_name to '+' or end it with '+'. For example, this will ensure that the User model won’t have a backwards relation to this model:

如何反向查询ManytoMany Django

how reverse query ManytoMany Django

django

reverse

m2m