python json模块方法函数

json模块就是用来处理json数据类型，主要用作网络传输。

# Python中的数据类型的格式
data = [
    {"id": 1, "name": "武沛齐", "age": 18},
    {"id": 2, "name": "alex", "age": 18},
    ('wupeiqi',123),
]
# JSON格式
value = '[{"id": 1, "name": "武沛齐", "age": 18}, {"id": 2, "name": "alex", "age": 18},["wupeiqi",123]]'

数据类型转json被称为序列化：

import json
data = [
    {"id": 1, "name": "武沛齐", "age": 18},
    {"id": 2, "name": "alex", "age": 18},
]
res = json.dumps(data)
print(res) # '[{"id": 1, "name": "\u6b66\u6c9b\u9f50", "age": 18}, {"id": 2, "name": "alex", "age": 18}]'
res = json.dumps(data, ensure_ascii=False)
print(res) # '[{"id": 1, "name": "武沛齐", "age": 18}, {"id": 2, "name": "alex", "age": 18}]'

json类型转数据类型被称为反序列化：

import json
data_string = '[{"id": 1, "name": "武沛齐", "age": 18}, {"id": 2, "name": "alex", "age": 18}]'
data_list = json.loads(data_string)
print(data_list)

python数据类型转json格式对数据类型有所要求，默认只支持dict,list,tuple,str,int,float,True,False,None
其他类型想要转换需要借助JSONEncoder才能实现
json模块常用的是：
json.dumps，序列化生成一个字符串
json.loads，发序列号生成python数据类型
json.dump，将数据序列化并写入文件

import json
data = [
    {"id": 1, "name": "武沛齐", "age": 18},
    {"id": 2, "name": "alex", "age": 18},
]
file_object = open('xxx.json', mode='w', encoding='utf-8')
json.dump(data, file_object)
file_object.close()

json.load，读取文件中的数据并反序列化为python的数据类型

import json
file_object = open('xxx.json', mode='r', encoding='utf-8')
data = json.load(file_object)
print(data)
file_object.close()