Python 常用函数 shelve

shelve模块比pickle模块简单，只有一个open函数，返回类似字典的对象，可读可写;key必须为字符串，而值可以是python所支持的数据类型；

写入文件：

import shelve
f=shelve.open(r'sheve.txt')
f['stu1_info']={'name':'egon','age':18,'hobby':['piao','smoking','drinking']}
f['stu2_info']={'name':'gangdan','age':53}
f['school_info']={'website':'http://www.pypy.org','city':'beijing'}
f.close()

读取文件：

import shelve
f = shelve.open('sheve.txt') 
print(f['stu1_info']) 
print(f['stu2_info'])
print(f['school_info'])
f.close()
结果：
{'name': 'egon', 'age': 18, 'hobby': ['piao', 'smoking', 'drinking']}
{'name': 'gangdan', 'age': 53}
{'website': 'http://www.pypy.org', 'city': 'beijing'}

修改文件：

#修改文件
import shelve
f=shelve.open(r'sheve.txt')
f['school_info']={'website':'http://www.baidu.com'}
f.close()
#查看文件
import shelve
f = shelve.open('sheve.txt')
print(f['stu1_info'])
print(f['stu2_info'])
print(f['school_info'])
f.close()
结果：
{'name': 'egon', 'age': 18, 'hobby': ['piao', 'smoking', 'drinking']}
{'name': 'gangdan', 'age': 53}
{'website': 'http://www.baidu.com'}