python：Json模块dumps、loads、dump、load介绍
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'>
