管理员操作-查询集以应用多对多 [英] Admin action- queryset to apply Many to Many

问题描述

如何使用admin操作创建将应用多对多值的查询集？

How do I use the admin action to create a queryset which will apply a Many-to-Many value?

我知道值必须已经存在（在我的情况下，颜色itels必须存在）。

I understand the 'value' will have to already exist (in my case, the colour itsel will have to exist).

模型

class Colours(models.Model):
    colour_name = models.CharField(max_length=50)

class Car(models.Model):
    brand = models.CharField(max_length=200)
    available_colours = models.ManyToManyField(Colours, blank=True)

Admin.py

class CarAdmin(admin.ModelAdmin):
    actions = ['Red']

尝试1：仅适用于FK

Attempt 1: only works for FK

def Red(self, request, queryset):
        queryset.update(colour=Colour.objects.get(colour_name__iexact='Red'), updated=timezone.now())

尝试2：无效

def Red(self, request, queryset):
    queryset.update = self.model._meta.app_label, self.model._meta.model_name

推荐答案

您可以在Django中分配关系集。

def Red(self, request, queryset):
    red_color = Colour.objects.get(colour_name__iexact='Red')
    queryset.update(available_colours=[red_color])

根据您的评论和到 docs ， django似乎不支持对许多网站进行批量更新。

according to your comment and to docs, it seems django doesnot support bulk update for manytomany fields.

您可以这样解决：

def Red(self, request, queryset):
    red_color = Colour.objects.get(colour_name__iexact='Red')
    for car in queryset:
        car.available_colours.add(red_color)

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