用pickle模块实现“增删改查”的简易功能

pickle的作用：

1：pickle.dump(dict,file)把字典转为二进制存入文件.

2：pickle.load(file)把文件二进制内容转为字典

import pickle

# 增
def adds():
    users = {"name":"yangbin", "age":22, "sex":"male"}
    with open("red.txt", "wb") as f:
        pickle.dump(users, f)
    dic = {}
    with open("red.txt") as sd:
        dic = pickle.load(sd)
    print dic

# 删
def deletes():
    dic = {}
    with open("red.txt") as f:
        dic = pickle.load(f)
    dic.pop("sex")
    with open("red.txt", "wb") as ff:
        pickle.dump(dic, ff)
    print dic 

# 改
def changes():
    dic = {}
    with open("red.txt") as f:
        dic = pickle.load(f)
    dic["age"] = 28
    with open("red.txt", "wb") as f:
        pickle.dump(dic, f)
    print dic

# 查
def finds():
    dic = {}
    with open("red.txt") as f:
        dic = pickle.load(f)
    print dic
    for k,v in dic.items():
        print "%s ---> %s" % (k, v)  

adds()
deletes()
changes()
finds()

运行结果:

root@python3:/python/python2/linshi# python 01.py
{'age': 22, 'name': 'yangbin', 'sex': 'male'}
{'age': 22, 'name': 'yangbin'}
{'age': 28, 'name': 'yangbin'}
{'age': 28, 'name': 'yangbin'}
age ---> 28
name ---> yangbin
root@python3:/python/python2/linshi#