python jason,pickle

时间:2023-03-09 19:05:50
python jason,pickle

参考官网 https://docs.python.org/3/library/json.html

https://docs.python.org/3/library/pickle.html

了解这两个模块首先要知道什么是序列化,反序列化

通常我们把变量从内存中变成可存储或传输的过程称之为序列化,序列化之后,就可以把序列化后的内容写入磁盘,或通过网络传输到别的机器上。

反过来,把变量内容从序列化的对象重新读到内存里称之为反序列化,即unpickling

区别

1,pickle是一个序列化在文件中存储,提取对象的python模块,json是处理json语言的模块

2,JSON只能处理基本数据类型。pickle能处理所有Python的数据类型。

3,JSON用于各种语言之间的字符转换。pickle用于Python程序对象的持久化或者Python程序间对象网络传输,但不同版本的Python序列化可能还有差异。

json

json序列化,将之转换为字符串

dumps,dump (区别:dumps将对象序列号,dump将对象序列号并保存到文件)

dumps

为了效果展现加了pprint模块

import json
import pprint
a={"b": "Hello","c":'好',"a": 'world'}
b=json.dumps(a,ensure_ascii=False,indent=4,separators=(',', ':'),sort_keys=True)
#ensure_ascii默认开启不加会将中文字符转义,indent缩进默认无,separators分隔符默认(',', ':')
print(b)
print (type(b))
pprint.pprint(b)

输出

python jason,pickle

dump

#coding=utf-8
import json
dict1={"b": "Hello","c":'好',"a": 'world'}
with open('1.txt','a') as f:
json.dump(dict1,f,ensure_ascii=False,indent=4,separators=(',', ':'),sort_keys=True)

json反序列化

load,loads(区别loads将序列号字符串反序列化,load将序列化字符串从文件读取并反序列化)

loads

import json
import pprint
a={"b": "Hello","c":'好',"a": 'world'}
b=json.dumps(a,ensure_ascii=False,indent=4,separators=(',', ':'),sort_keys=True)
#ensure_ascii默认开启不加会将中文字符转义,indent缩进默认无,separators分隔符默认(',', ':')
c=json.loads(b,encoding='utf-8')
pprint.pprint(b)
pprint.pprint(c)

输出

python jason,pickle

load

#coding=utf-8
import json
import pprint
with open('1.txt','r',encoding='utf-8') as f:
a=json.load(f)
pprint.pprint(a)

输出

python jason,pickle

pickle模块

同样拥有dumps,dump,load,loads

dumps与loads

#coding=utf-8
import pickle
import pprint
dict1={"b": "Hello","c":'好',"a": 'world'}
a=pickle.dumps(dict1)
print(type(a))
pprint.pprint(a)
b=pickle.loads(a,encoding='utf-8')
pprint.pprint(b)
print(type(b))

输出

python jason,pickle

dump与load

#coding=utf-8
import pickle
import pprint
dict1={"b": "Hello","c":'好',"a": 'world'}
with open('1.txt','wb') as f:
pickle.dump(dict1,f)
with open('1.txt', 'rb') as f:
data = pickle.load(f)
pprint.pprint(data)

输出

python jason,pickle

shelve模块

import shelve
f=shelve.open('3.txt')
f['info']={'name':'liu','age':''}
#f['mode']={'txt'}
p=f.get('info')
q=f['info']['name']
print (p,q)