python中的Json模块dumps、dump、loads、load函数用法详解

import json
data= {'a':'1111','b':'2222','c':'3333','d':'4444'} 
filename = r"d:\1.json"  

# 使用dumps()
str_data = json.dumps(data) 
print(str_data)   #输出{"a": "1111", "b": "2222", "c": "3333", "d": "4444"}

# 使用loads()
dict_data = json.loads(str_data)
print(dict_data)  #输出{'a': '1111', 'b': '2222', 'c': '3333', 'd': '4444'} 

import json
data = {'a':'1111','b':'2222','c':'3333','d':'4444'}
filename = r"d:\1.json"  

# 使用dump()写入一行数据
with open(filename, "w") as f:
    json.dump(data,f)

# 使用load()读取一行数据
with open(filename, 'r') as f:
    jsObj = json.load(f)
for key in jsObj.keys(): 
    print('key: %s value: %s' % (key,jsObj.get(key)))

import json

filename = r"d:\1.json"  
data = [{'a':'1111','b':'2222','c':'3333','d':'4444'},
        {'e':'1111','f':'2222','g':'3333','h':'4444'},
        {'i':'1111','j':'2222','k':'3333','l':'4444'},
        {'m':'1111','n':'2222','o':'3333','p':'4444'}]

#写入多行数据到文件
with open(filename,'w') as f:
    for i in range(len(data)):
        f.write(json.dumps(data[i])+'\n')  #一定要换行

#从文件读取多行数据,并转化为list
with open(filename,'r') as f:
    jsObj=[json.loads(line) for line in f]
print(jsObj)