Python使用shelve模块实现简单数据存储的方法


            本文实例讲述了Python使用shelve模块实现简单数据存储的方法。分享给大家供大家参考。具体分析如下：

Python的shelve模块提供了一种简单的数据存储方案，以dict（字典）的形式来操作数据。





#!/usr/bin/python

import sys, shelve

def store_person(db):

  """

  Query user for data and store it in the shelf object

  """

  pid = raw_input('Enter unique ID number:')

  person = {}

  person['name'] = raw_input('Enter name:')

  person['age'] = raw_input('Enter age:')

  person['phone'] = raw_input('Enter phone number:')

  db[pid] = person

def lookup_person(db):

  """

  Query user for ID and desired field, 

  and fetch the corresponding data 

  from the shelf object

  """

  pid = raw_input('Enter unique ID number:')

  temp = db[pid]

  field = raw_input('Please enter name, age or phone:')

  field.strip().lower()

  print field.capitalize() + ': ', temp[field]

def print_help():

  print 'The avaliable commands are:'

  print 'store  :Stores infomation about a person'

  print 'lookup  :Looks up a person form ID number'

  print 'quit   :Save changes and exit'

  print '?    :Prints this message'

def enter_command():

  cmd = raw_input('Enter command(? for help):')

  cmd = cmd.strip().lower()

  return cmd

def main():

  database = shelve.open('database')

  # database stores in current directory

  try:

    while True:

      cmd = enter_command()

      if cmd == 'store':

        store_person(database)

      elif cmd == 'lookup':

        lookup_person(database)

      elif cmd == '?':

        print_help()

      elif cmd == 'quit':

        return

  finally:

    database.close()

    # Close database in any condition

if __name__ == '__main__':

  main()







希望本文所述对大家的Python程序设计有所帮助。