python练手程序-通许录

需要注意的几点：

1.list的初始化

2.cPickle的load和dump方法的使用

3.class的存储

4.sort函数的使用

5.global标签的使用

6.初始的时候不存在memberlist.data或者文件内容为空解决方法

  1 #Filename:MyAddressBook.py
  2 import cPickle as p
  3 import os
  4 #Class Item
  5 class Item:
  6     def __init__(self,name,age,gender):
  7         self.name = name
  8         self.age = age
  9         self.gender = gender
 10 #the main menu of address book   
 11 def menu():
 12     '''the main menu of address book'''
 13     print ''
 14     print '1.Insert an item'
 15     print '2.Delete an item'
 16     print '3.Modify an item'
 17     print '4.Display all items'
 18     print '5.Sort all items'
 19     print '6.Exit the program'
 20     print 'What do you want to do?'
 21     
 22 #initialization of system, load the member list
 23 def begin():
 24     '''initialization of system, load the member list'''
 25     global itemlist
 26     if os.path.exists('memberlist.data') == True:#to judge whether the file exists
 27         listfile = file('memberlist.data','r')
 28         if len(listfile.read())!=0:#to judge whether the file is empty
 29             itemlist = p.load(listfile)        
 30         listfile.close()
 31 #exitance of system, store the menber list
 32 def end():
 33     '''exitance of system, store the menber list'''
 34     global itemlist
 35     listfile = file('memberlist.data','w+')
 36     p.dump(itemlist,listfile)
 37     listfile.close()
 38 #insert an item into the member list   
 39 def insert():
 40     '''insert an item into the member list'''
 41     name = raw_input('Enter name:')
 42     age = int(raw_input('Enter age:'))
 43     gender = raw_input('Enter gender:')
 44     item = Item(name,age,gender)
 45     global itemlist
 46     itemlist.append(item)
 47 #print an item
 48 def output(item):
 49     '''print an item'''
 50     print '%-15s%-5d%s'%(item.name,item.age,item.gender)
 51 #print all items       
 52 def display():
 53     '''print all items'''
 54     global itemlist
 55     l = len(itemlist)
 56     print 'name           age  gender'
 57     for i in range(0,l):
 58         output(itemlist[i])
 59     print ''
 60 #delete an item by name from member list
 61 def delete():
 62     '''delete an item by name from member list'''
 63     name = raw_input('Enter the name you want to delete:')
 64     global itemlist
 65     l = len(itemlist)
 66     for i in range(0,l):
 67         if (itemlist[i].name == name):
 68             itemlist.pop(i)
 69 #update an item
 70 def update(item):
 71     '''update an item'''
 72     item.name = raw_input('Enter name:')
 73     item.age = int(raw_input('Enter age:'))
 74     item.gender = raw_input('Enter gender:')
 75 #update an item's information by name 
 76 def modify():
 77     '''update an item's information by name'''
 78     name = raw_input('Enter the name you want to modify:')
 79     global itemlist
 80     l = len(itemlist)
 81     for i in range(0,l):
 82         if (itemlist[i].name == name):
 83             update(itemlist[i])
 84     print 'Update done!'
 85 #sort all items by name
 86 def sort():
 87     global itemlist
 88     itemlist.sort(None,key = lambda item:item.name)
 89 #Here are the scripts
 90 itemlist = [] #Notice here!!!
 91 begin()
 92 while True:
 93     menu()
 94     sel = int(raw_input())
 95     if sel == 1:
 96         insert()
 97     elif sel == 2:
 98         delete()
 99     elif sel == 3:
100         modify()
101     elif sel == 4:
102         display()
103     elif sel == 5:
104         sort()
105     else:
106         break
107 end()
108 print 'Good Bye!'