python：Json模块dumps、loads、dump、load介绍

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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

import json

dict = {'a': 'wo', 'b': 'zai', 'c': 'zhe', 'd': 'li'}
string = json.dumps(dict)
print(dict)
print(string)
print(type(dict))
print(type(string))

with open(r'C:\Users\zy\Documents\GitHub\python3\searchTest\json.json','w')as f:
    f.write(string)

{'a': 'wo', 'b': 'zai', 'c': 'zhe', 'd': 'li'}
{"a": "wo", "b": "zai", "c": "zhe", "d": "li"}
<class 'dict'>
<class 'str'>

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

import json

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

{'a': 'wo', 'b': 'zai', 'c': 'zhe', 'd': 'li'}
Traceback (most recent call last):
<class 'dict'>
  File "C:/Users/zy/Documents/GitHub/python3/searchTest/json_test.py", line 11, in <module>
    f.write(dict)
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

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

举例结果：

{
    "code": "200",
    "message": "",
    "redirect": "",
    "value": {
        "name": "so",
        "title": "360",
        "value": "2"
    }
}

 

2.json.loads():用于将str类型的数据转成dict

dict = {'a': 'wo', 'b': 'zai', 'c': 'zhe', 'd': 'li'}
dumps = json.dumps(dict)
loads = json.loads(dumps)

print(dict)
print(dumps)
print(loads)

print(type(dict))
print(type(dumps))
print(type(loads))

{'a': 'wo', 'b': 'zai', 'c': 'zhe', 'd': 'li'}
{"a": "wo", "b": "zai", "c": "zhe", "d": "li"}
{'a': 'wo', 'b': 'zai', 'c': 'zhe', 'd': 'li'}
<class 'dict'>
<class 'str'>
<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

dict = {'a': 'wo', 'b': 'zai', 'c': 'zhe', 'd': 'li'}
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

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

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