使用注释时在Django中显示选择字段的名称 [英] Display name of a choice field in Django while using annotate

问题描述

使用注释时，我试图获取选项的显示名称，但我一直无法弄清楚。我有以下查询：

I am trying to get display names of choices when using annotate, but I haven't been able to figure out. I have the following query:

Survey.objects.values('what').annotate(count=Count('why')).order_by()

结果为：

[{'count': 34, 'what': u'a'}, 
{'count': 39, 'what': u'c'}, 
{'count': 40, 'wat': u'p'}]

但是我想要一些显示选择字段名称而不是键的东西：

But I want something that displays the name of the choice field and not the key:

[{'count': 34, 'what': u'appreciative'}, 
{'count': 39, 'what': u'creative'}, 
{'count': 40, 'wat': u'promising'}]

我尝试了get_what_display（如文档中提到的和该主题的其他stackoverflow答案中所述） ，但django引发错误。即以下内容似乎无效

I tried get_what_display (as mentioned on the docs and other stackoverflow answers on this topic), but django throws an error. i.e the following doesn't seem to work

Survey.objects.values('get_what_display').annotate(count=Count('why')).order_by()

推荐答案

前面说过， get_FOO_display 是一个实例方法，不是您可以在 .values（）中使用的方法。因此，我将采用Python方式来完成您想做的事情：

As it's said earlier, get_FOO_display is an instance method, not something that you can use in .values(). Thus, I'd go with Pythonic way to accomplish what you'd like to do:

from django.utils.encoding import force_text

survey_counts = Survey.objects.values('what').annotate(count=Count('why')).order_by()

choices = dict(Survey._meta.get_field_by_name('what')[0].flatchoices)
for entry in survey_counts:
    entry['what'] = force_text(choices[entry['what']], strings_only=True)

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