定義序列化器（本質就是一個類），一般包括模型類的字段，有自己的字段類型規則。實現了序列化器後，就可以創建序列化對象以及查詢集進行序列化操作，通過序列化對象.data來獲取數據（不用自己構造字典，再返回Json數據）

廢話不多說，直接上代碼！！！

DRF序列化可以理解這幾句

                    - 導入模塊：from rest_framework import serializers
                    - 建立一個序列化類
                        class BookSerializer(serializers.Serializer):
                            字段可以自定義
                            
                    
 
- 獲取客戶端請求數據
                    - 開始序列化
                        serialized_data = BookSerializer(origin_data, many=True)
                    - 寫入數據庫
                    - 獲取序列化後的數據，返回給客戶端
                        return Response(serialized_data.data)

1.接口設計：

　　　　　　　　　 GET       127.0.0.1:8000/books/     #
 
 獲取所有數據，返回值: [{}, {}]
                GET       127.0.0.1:8000/books/{id} # 獲取一條數據，返回值：{}
                POST      127.0.0.1:8000/books/     # 新增一條數據，返回值：{}
                PUT       127.0.0.1:8000/books/{id} # 修改數據，返回值：{}
                DELETE    127.0.0.1:8000/books/{id} # 刪除數據，返回空

2.創建新的項目

models.py
#表
class Author(models.Model):
    nid 
 
= models.AutoField(primary_key=True)
    name = models.CharField(max_length=32)
    age = models.IntegerField()

    def __str__(self):
        return self.name


class Publish(models.Model):
    nid = models.AutoField(primary_key=True)
    name = models.CharField(max_length=32)
    city = models.CharField(max_length=32)
    email = models.EmailField()

    def __str__(self):
        return self.name


class Book(models.Model):
    nid = models.AutoField(primary_key=True)
    title = models.CharField(max_length=32)
    price = models.DecimalField(max_digits=5, decimal_places=2)
    # 外鍵字段
    publish = models.ForeignKey(to="Publish", related_name="book", related_query_name="book_query", on_delete=models.CASCADE)
    # 多對多字段
    authors = models.ManyToManyField(to="Author")

3進行數據的遷移執行命令

python manage.py makemigrations
python manage.py migrate

4.開始創建視圖和路由

urls.py
from django.contrib import admin
from django.urls import path
from app1 import views

urlpatterns = [
    path(‘admin/‘, admin.site.urls),
    path(‘books/‘,views.BookView.as_view()),
]




views.py
from rest_framwork.views import APIView
from rest_framwork import serializers
from rest_fromwork.response import Response

class BookView(APIView):
    def get(self,request):
        book_list = Book.objects.all()
        # print(book_list)
#進行數據的序列化
        serializer_book_list = BookSerializer(book_list,many=True)
#返回的時候必須帶著data，因為所有的數據都在data裏
        return Response(serializer_book_list.data)

    def post(self,request):
        pass

5.創建序列化的類

urls.py
calss BookSerializer(serializers,Serializer):
    title = serializers.CharField(max_length=32)
    price = serializers.DecimalField(max_digits=5,decimal_places=2)
    publish = serializers.CharField(max_length=32)
    author= serializers.CharField(max_length=32)

6.註意，現在的頁面是這樣的

7.改進的辦法，也就是說我們序列化的重頭戲‘

url.py

class BookSerializer(serializers.Serializer):
    title = serializers.CharField(max_length=32)
    price = serializers.DecimalField(max_digits=5,decimal_places=2)
    publish = serializers.CharField(max_length=32)
    #這裏必須是用SerializerMethodField()！！！
    authors_list = serializers.SerializerMethodField()
#方法裏有一個get_方法，註意！！！authors_list必須和上邊的序列化一致否則報錯找不到對應的方法！
    def get_authors_list(self,book_obj):
        author_list = list()
        for author in book_obj.authors.all():
            author_list.append(author.name)
        return author_list

’

DRF-->1 序列化組件的使用和接口設計---get