django序列化 serializers

DRF的核心 就是 前后端分离的核心

前后端分离开发的核心：
将模型转换为json 称之为 序列化
将json转换为模型 称之为 反序列化

Django的序列化工具让你可以将Django的模型‘翻译’成其它格式的数据。通常情况下，这种其它格式的数据是基于文本的，并且用于数据交换\传输过程。

序列化数据

Django为我们提供了一个强大的序列化工具serializers。使用它也很简单，如下所示：

from django.core import serializers
data = serializers.serialize("xml", SomeModel.objects.all())

data = serializers.serialize("json", Author.objects.all())
print(data)

[{"model": "index.author", "pk": 1, "fields": {"name": "pfeiliu", "age": 19, "email": "789@163.com", "isActive": false}}, {"model": "index.author", "pk": 5, "fields": {"name": "lao wei", "age": 18, "email": "123@qq.com", "isActive": true}}, {"model": "index.author", "pk": 6, "fields": {"name": "WangDB", "age": 36, "email": "wangdb@163.com", "isActive": false}}, {"model": "index.author", "pk": 7, "fields": {"name": "WangDB", "age": 36, "email": "wangdb@163.com", "isActive": false}}, {"model": "index.author", "pk": 8, "fields": {"name": "WangDB", "age": 36, "email": "wangdb@163.com", "isActive": false}}, {"model": "index.author", "pk": 9, "fields": {"name": "WangDB", "age": 36, "email": "wangdb@163.com", "isActive": false}}, {"model": "index.author", "pk": 10, "fields": {"name": "WangDB", "age": 36, "email": "wangdb@163.com", "isActive": false}}, {"model": "index.author", "pk": 11, "fields": {"name": "WangDB", "age": 36, "email": "wangdb@163.com", "isActive": false}}, {"model": "index.author", "pk": 12, "fields": {"name": "WangDB", "age": 36, "email": "wangdb@163.com", "isActive": false}}, {"model": "index.author", "pk": 13, "fields": {"name": "WangDB", "age": 36, "email": "wangdb@163.com", "isActive": false}}, {"model": "index.author", "pk": 14, "fields": {"name": "WangDB", "age": 36, "email": "wangdb@163.com", "isActive": false}}]

 

首先，从djang.core导入它，然后调用它的serialize方法，这个方法至少接收两个参数，第一个是你要序列化成为的数据格式，这里是‘xml’，第二个是要序列化的数据对象，数据通常是ORM模型的QuerySet，一个可迭代的对象。

就是这么简单！！

序列化指定字段

如果你不想序列化模型对象所有字段的内容，只想序列化某些指定的字段，可以使用fields参数，如下所示：

from django.core import serializers
data = serializers.serialize('xml', SomeModel.objects.all(), fields=('name','size'))

data = serializers.serialize("json", Author.objects.all(),fields=('name','age'))
print(data)

[{"model": "index.author", "pk": 1, "fields": {"name": "pfeiliu", "age": 19}}, {"model": "index.author", "pk": 5, "fields": {"name": "lao wei", "age": 18}}, {"model": "index.author", "pk": 6, "fields": {"name": "WangDB", "age": 36}}, {"model": "index.author", "pk": 7, "fields": {"name": "WangDB", "age": 36}}, {"model": "index.author", "pk": 8, "fields": {"name": "WangDB", "age": 36}}, {"model": "index.author", "pk": 9, "fields": {"name": "WangDB", "age": 36}}, {"model": "index.author", "pk": 10, "fields": {"name": "WangDB", "age": 36}}, {"model": "index.author", "pk": 11, "fields": {"name": "WangDB", "age": 36}}, {"model": "index.author", "pk": 12, "fields": {"name": "WangDB", "age": 36}}, {"model": "index.author", "pk": 13, "fields": {"name": "WangDB", "age": 36}}, {"model": "index.author", "pk": 14, "fields": {"name": "WangDB", "age": 36}}]