我应该怎么做才能使用映射 filter() 函数结果的字典？

Question

我有这样一个模型：

class BNetworkEdge(models.Model):
    id = models.AutoField(unique=True, primary_key=True)
    source = models.IntegerField()
    target = models.IntegerField()
    edge_type = models.IntegerField()

    class Meta:
        managed = True
        db_table = 'b_network_edge'

我有这样的字典：

{0:'direct', 1:'no-direct'}

我运行这个在pythonshell

>>> BNetworkEdge.objects.filter()[0].edge_type
0

如何得到 'direct' 而不是 '0' 的结果？

谢谢！

Answer 1

为了在您的视图中获得字典映射结果，您将执行如下操作：

#Your models.py 
class BNetworkEdgeManager(models.Manager):
    def get_queryset(self):
        # The return of query by manager 
        return list(super().get_queryset().values('id', 'data_dict'))


class BNetworkEdge(models.Model):
    id = models.AutoField(unique=True, primary_key=True)
    source = models.IntegerField()
    target = models.IntegerField()
    edge_type = models.IntegerField()
    objects = BNetworkEdgeManager()

# This goes in views.py 

from .models import BNetworkEdge
def bnetwork_edge_view(request):
    # this context to holds your data as a dictionary
    context  = {}
    dict_data = BNetworkEdge.objects.all()
    context = {'dict_data':dict_data}
    # You can print the content of your context variable 
    # to see the dictionary objects 
    print(context)
    return render(request,"Put Your Html Template Here eg.('network.html/')",context)

另外，要将 edge_type 的值作为字典获取，您需要创建一个方法来将 edge_type 句柄作为字典获取，并将它们 link 与属性装饰器！因此：


class BNetworkEdge(models.Model):
    id = models.AutoField(unique=True, primary_key=True)
    source = models.IntegerField()
    target = models.IntegerField()
    edge_type = models.IntegerField()
    objects = BNetworkEdgeManager()
    
    @property
    def get_edge_type(self):
        dict_values = {0:'dict_data', 1:'data'}
        return dict_values[self.edge_type]
   
# Then you call this in your terminal: 
BNetworkEdge.objects.filter()[0].get_edge_type()

#which returns:
[output] {0: 'dict_data'}

Answer 2

您可以为此创建一个 property 作为，

@property
def edge_type_value(self):
    _vals = {0:'direct', 1:'no-direct'}
    return _vals[self.edge_type]

你的代码就像，

from django.db import models

class BNetworkEdge(models.Model):
    id = models.AutoField(unique=True, primary_key=True)
    source = models.IntegerField()
    target = models.IntegerField()
    edge_type = models.IntegerField()

    class Meta:
        managed = True
        db_table = 'b_network_edge'

    @property
    def edge_type_value(self):
        _vals = {0:'direct', 1:'no-direct'}
        return _vals[self.edge_type]

您可以访问它，

In [10]: BNetworkEdge.objects.filter()[0].edge_type_value
Out[10]: 'direct'

Answer 3

在您的字段中添加适当的选项choices

class BNetworkEdge(models.Model):

    class EdgeTypes(models.IntegerChoices):
        DIRECT = 1, 'direct'
        NO_DIRECT = 2, 'no-direct'

    id = models.AutoField(unique=True, primary_key=True)
    source = models.IntegerField()
    target = models.IntegerField()
    edge_type = models.IntegerField(choices=EdgeTypes.choices)

    class Meta:
        managed = True
        db_table = 'b_network_edge'

然后您可以调用 get_edge_type_display 来获取选择标签

BNetworkEdge.objects.filter()[0].get_edge_type_display()

我应该怎么做才能使用映射 filter() 函数结果的字典？

What should I do so that I can use a dictionary mapping the filter() function result?

python

django

django-models