在Django项目显示从views.py表

Question

<table class="table"> 
    <thead> 
    <tr> 
      <th>School</th> 
      <th>Strength</th> 
      <th>Average</th> 
    </tr> 
    </thead> 
    <tbody> 
    {% for school in cluster.school_set.all %} 
      <tr> 
       <td><a href="{% url 'data:school_detail' state.id region.id cluster.id school.id %}">{{ school.school_name }}</a></td> 
       <td>{{ school.strength }}</td> 
       <td>school average</td> 
      </tr> 
     {% endfor %} 
     </tbody> 
</table> 

这是在我的模板中的表，它表明在群集中的所有学校的详细信息（市/镇）以表格形式：1）学校名称列2）学校力量3）学校平均分数从一定数量的考试。 我可以很容易地得到列的数据1）学校名称& 2）学校的实力，因为他们只是上课的领域。问题在于列平均值。为了获得平均水平，我需要有一些我无法直接在模板中完成的代码。问题是我不知道如何在views.py中做到这一点。来计算，我需要school.id，但从URL我只得到cluster.id 在这些情况下，你不能简单地从views.py中获取数据，而不从模板中给出值怎么办？

set = Average.objects.filter(school=school.id): 
obj = set.latest('average_date') 
avg = obj.average_value 

这些是我需要得到一个特定学校的平均代码行。

class School(models.Model): 
    state = models.ForeignKey(State, on_delete=models.CASCADE) 
    region = ChainedForeignKey(Region, chained_field="state",chained_model_field="state", show_all=False, auto_choose=True, sort=False, on_delete=models.CASCADE) 
    cluster = ChainedForeignKey(Cluster, chained_field="region",chained_model_field="region", show_all=False, auto_choose=True, sort=False, on_delete=models.CASCADE) 
    school_name = models.CharField(max_length=250) 
    facilitator = models.CharField(max_length=250) 
    f_number = models.IntegerField() 
    f_email = models.EmailField() 
    school_logo = models.FileField(default='') 
    strength = models.IntegerField() 

    def __str__(self): 
     return self.school_name 


class Avergae(models.Model): 
    state = models.ForeignKey(State, on_delete=models.CASCADE) 
    region = ChainedForeignKey(Region, chained_field="state",chained_model_field="state", show_all=False, auto_choose=True, sort=False, on_delete=models.CASCADE) 
    cluster = ChainedForeignKey(Cluster, chained_field="region",chained_model_field="region", show_all=False, auto_choose=True, sort=False, on_delete=models.CASCADE) 
    school = ChainedForeignKey(School, chained_field="cluster",chained_model_field="cluster", show_all=False, auto_choose=True, sort=False, on_delete=models.CASCADE) 
    average_date = models.DateField() 
    average_value = models.DecimalField(max_digits=4, decimal_places=2) 
    average_attendance = models.IntegerField() 
    average_note = models.CharField(max_length=250) 

    def __str__(self): 
     return '{}: {}'.format(self.average_date, self.average_value) 

这些都是我的模特学校和平均

Answer 1

在你School模型，你可以写一个方法get_average：

class School(models.Model): 
    # other fields 
    def get_average(self): 
     return self.avergae_set.latest('average_date').average_value 

然后在模板你可以这样做：

{{ school.get_average }} 

注意：您的平均型号拼写错误，您有Avergae而应该是Average