ManyToManyField的应用实例

1，简单示例：

class TestAdmin(admin.ModelAdmin): 
    def get_some_value(self): 
     return ", " . join([x.__str__() for x in self.manytomany_field.all()]) 

    list_display(get_some_value) 
    get_some_value.short_description = 'Title' #sets column header to Title 

2，实际应用代码：

#显示选择的合作区域，此处的city为本模型下manytomany字段
    def post_tag(self):
        return [pt.__str__() for pt in self.city.all()]
    post_tag.short_description = '标签'
    filter_horizontal = ('tags',)  # 多对多，穿梭框（横向双排，左边选到右边）

3，将ManyToManyField显示为复选框

from django.db import models
from django.contrib import admin
from django.forms import CheckboxSelectMultiple

class MyModelAdmin(admin.ModelAdmin):
    formfield_overrides = {
        models.ManyToManyField: {'widget': CheckboxSelectMultiple},
    }

4，还有2种方法可尝试：

def formfield_for_manytomany(self, db_field, request=None, **kwargs):
    if db_field.name == 'your field name':
        kwargs['widget'] = form_widgets.CheckboxSelectMultiple()
        kwargs['help_text'] = ''

    return db_field.formfield(**kwargs)

def get_form(self, request, obj=None, **kwargs):
    form = super(VNodeAdmin, self).get_form(request, obj, **kwargs)
    form.base_fields['node_type'].widget = forms.CheckboxSelectMultiple()
    return form

5，给复选框的内容加上CSS样式：

def post_tag(self):
        result = []
        for pt in self.city.all():
            result.append(f'''
            <span class="el-tag el-tag--small el-tag--success el-tag--dark">{pt.name} </span>
            '''
            )
        return format_html("".join(result))

样式具体如图：