如何在django中获取相关集合（多对多字段）

我有一个员工模型

class Employees(models.Model):
name = models.CharField(max_length=200, help_text="Enter the name of the employee")
location = models.ManyToManyField('Coverage')

def __str__(self):
    return self.name'

和一个位置模型

class Coverage(models.Model):
name = models.CharField(max_length=300, help_text="Enter employee location")
time_needed = models.IntegerField(help_text="Enter time needed to get to work. eg (40 = > 40 minutes)")

def __str__(self):
    return self.name

如何使用（employees=employees.objects.all（））从模板中访问所需的覆盖率时间

我试过

{{employees.location.time}}

，但不起作用。任何好的答复都将不胜感激

---

ps：这只是一个更大模型类的一个片段，employees=employees.objects.all（）是一个查询集，您不能用它访问字段。但是，如果您对它进行迭代，您将可以访问每个实例，然后您将能够拥有任何实例的

location

。因为

location

是一个ManyToManyField

location=models.ManyToManyField（'location'）

。您还需要对其进行迭代

{% for employee in employees %}
    {{ employee.location.all }} // Location queryset

    {% for location in employee.location.all %}
          {{ location.time_needed }}
    {% endfor %}
{% endfor %}

如果您真的不需要遍历这些字段。您可以使用

slice

选择一个实例

{{employees.0}

将根据查询集顺序选择第一个employees实例

{{employee.0.location.all.0}

根据查询集顺序选择第一个位置实例

{{employee.0.location.all.0.time_needed}

将允许您访问该值

或者更清楚：

{% with employees.0 as employee %}
     {% with location as employee.location.all.0 %}
         {{ location.time_needed }}
     {% endwith %}
{% endwith %}

---

employees=employees.objects.all（）。但是，如果您对它进行迭代，您将可以访问每个实例，然后您将能够拥有任何实例的
location
。因为
location
是一个ManyToManyField
location=models.ManyToManyField（'location'）
。您还需要对其进行迭代

{% for employee in employees %}
    {{ employee.location.all }} // Location queryset

    {% for location in employee.location.all %}
          {{ location.time_needed }}
    {% endfor %}
{% endfor %}

如果您真的不需要遍历这些字段。您可以使用
slice
选择一个实例

{{employees.0}
将根据查询集顺序选择第一个employees实例

{{employee.0.location.all.0}
根据查询集顺序选择第一个位置实例

{{employee.0.location.all.0.time_needed}
将允许您访问该值

或者更清楚：

{% with employees.0 as employee %}
     {% with location as employee.location.all.0 %}
         {{ location.time_needed }}
     {% endwith %}
{% endwith %}

我想，你可以这样做：

employees = Employees.objects.all()
for employee in employees:
   for location in employee.location.all():
      print(location.time_needed)

Coverage.objects.filter(id__in=employee.location.all().values('id')).values('time_needed')
# This will return time_needed of all the Coverage whose id matched the location ids of employee

如果您想访问特定的覆盖范围，则可以执行以下操作：

employees = Employees.objects.all()
for employee in employees:
   for location in employee.location.all():
      print(location.time_needed)

Coverage.objects.filter(id__in=employee.location.all().values('id')).values('time_needed')
# This will return time_needed of all the Coverage whose id matched the location ids of employee

我想，你可以这样做：

employees = Employees.objects.all()
for employee in employees:
   for location in employee.location.all():
      print(location.time_needed)

Coverage.objects.filter(id__in=employee.location.all().values('id')).values('time_needed')
# This will return time_needed of all the Coverage whose id matched the location ids of employee

如果您想访问特定的覆盖范围，则可以执行以下操作：

employees = Employees.objects.all()
for employee in employees:
   for location in employee.location.all():
      print(location.time_needed)

Coverage.objects.filter(id__in=employee.location.all().values('id')).values('time_needed')
# This will return time_needed of all the Coverage whose id matched the location ids of employee

我看不出这两个模型之间有任何联系
location=models.ManyToManyField（'location'）
location

model在哪里？感谢您指出这一点。我会更新模型。我看不到这两个模型之间有任何联系

location=models.ManyToManyField（'location'）

locationmodel在哪里？感谢您指出这一点。我会更新模型