python：Json模块dumpsloadsdumpload介绍

Posted 2020-11-05 Shapelei

 转载请注明出处：https://www.cnblogs.com/shapeL/p/9037670.html

由上篇文章（python3+requests：get/post请求）涉及到的json.dumps()扩展

1.json.dumps()用于将dict类型的数据转成str

备注：文件路径前面加上 r 是为了避免转义

 1 import json
 2 
 3 dict = {\'a\': \'wo\', \'b\': \'zai\', \'c\': \'zhe\', \'d\': \'li\'}
 4 string = json.dumps(dict)
 5 print(dict)
 6 print(string)
 7 print(type(dict))
 8 print(type(string))
 9 
10 with open(r\'C:\\Users\\zy\\Documents\\GitHub\\python3\\searchTest\\json.json\',\'w\')as f:
11     f.write(string)

1 {\'a\': \'wo\', \'b\': \'zai\', \'c\': \'zhe\', \'d\': \'li\'}
2 {"a": "wo", "b": "zai", "c": "zhe", "d": "li"}
3 <class \'dict\'>
4 <class \'str\'>

如果没有进行转换，则会报错：TypeError: write() argument must be str, not dict

1 import json
2 
3 dict = {\'a\': \'wo\', \'b\': \'zai\', \'c\': \'zhe\', \'d\': \'li\'}
4 with open(r\'C:\\Users\\zy\\Documents\\GitHub\\python3\\searchTest\\json.json\',\'w\')as f:
5     f.write(dict)

1 {\'a\': \'wo\', \'b\': \'zai\', \'c\': \'zhe\', \'d\': \'li\'}
2 Traceback (most recent call last):
3 <class \'dict\'>
4   File "C:/Users/zy/Documents/GitHub/python3/searchTest/json_test.py", line 11, in <module>
5     f.write(dict)
6 TypeError: write() argument must be str, not dict

 json.dumps()参数解释：常用参数解释

indent：应该是一个非负的整型，如果是0，或者为空，则一行显示数据；否则会换行且按照indent的数量显示前面的空白

sort_keys：将数据根据keys的值进行排序

1 response = requests.post(url=url,headers=headers).json()
2 print(json.dumps(response,sort_keys=True,indent=4))

举例结果：

 1 {
 2     "code": "200",
 3     "message": "",
 4     "redirect": "",
 5     "value": {
 6         "name": "so",
 7         "title": "360",
 8         "value": "2"
 9     }
10 }

 

2.json.loads():用于将str类型的数据转成dict

 1 dict = {\'a\': \'wo\', \'b\': \'zai\', \'c\': \'zhe\', \'d\': \'li\'}
 2 dumps = json.dumps(dict)
 3 loads = json.loads(dumps)
 4 
 5 print(dict)
 6 print(dumps)
 7 print(loads)
 8 
 9 print(type(dict))
10 print(type(dumps))
11 print(type(loads))

1 {\'a\': \'wo\', \'b\': \'zai\', \'c\': \'zhe\', \'d\': \'li\'}
2 {"a": "wo", "b": "zai", "c": "zhe", "d": "li"}
3 {\'a\': \'wo\', \'b\': \'zai\', \'c\': \'zhe\', \'d\': \'li\'}
4 <class \'dict\'>
5 <class \'str\'>
6 <class \'dict\'>

 

3.json.dump()用于将dict类型的数据转成str，并写入到json文件中

1 dict = {\'a\': \'wo\', \'b\': \'zai\', \'c\': \'zhe\', \'d\': \'li\'}
2 json.dump(dict,open(r\'C:\\Users\\zy\\Documents\\GitHub\\python3\\searchTest\\json.json\',\'w\'))

 

4.json.load()用于从json文件中读取数据

1 filename = (r\'C:\\Users\\zy\\Documents\\GitHub\\python3\\searchTest\\json.json\')
2 jsObj = json.load(open(filename))
3 print(jsObj)
4 print(type(jsObj))

1 {\'a\': \'wo\', \'b\': \'zai\', \'c\': \'zhe\', \'d\': \'li\'}
2 <class \'dict\'>