genericforeignkey django code example

Example 1: django genericforeignkey null

class MyModel(models.Model):
    ...other fields...
    content_type = models.ForeignKey(ContentType, blank=True, null=True, on_delete=models.SET_NULL)
    object_id = models.PositiveIntegerField(blank=True, null=True)
    content_object = generic.GenericForeignKey('content_type', 'object_id')

Example 2: django content type

from django.contrib.contenttypes.fields import GenericForeignKey
from django.contrib.contenttypes.models import ContentType
from django.db import models

class TaggedItem(models.Model):
    tag = models.SlugField()
    content_type = models.ForeignKey(ContentType, on_delete=models.CASCADE)
    object_id = models.PositiveIntegerField()
    content_object = GenericForeignKey('content_type', 'object_id')

    def __str__(self):
        return self.tag