Python中的字典操作

'''
Created on 2011-11-1
@author: dudong0726
python中所谓的字典其实就是java中的map，操作类似
'''

if __name__ == '__main__':
    ab = { 'Swaroop'   : '[e-mail]',
             'Larry'     : '[e-mail]',
             'Matsumoto' : '[e-mail]',
             'Spammer'   : '[e-mail]'
             }

    print("Swaroop's address is %s" % ab['Swaroop'])

    # Adding a key/value pair
    ab['Guido'] = '[e-mail]'    #通过key引用，如果key不存在，为添加新项
    
    # Deleting a key/value pair            
    del ab['Spammer']                   #通过key删除项

    # Modify a key/Value pair
    ab['Larry'] = 'Larry [e-mail]';   #修改某一项内容
    
    print ('\nThere are %d contacts in the address-book\n' % len(ab))
    for name,address in ab.items():
        print('Contact %s at %s' % (name,address))           #遍历ab，返回类似于集合的对象,


    if 'Guido' in ab: # OR ab.has_key('Guido')
        print ("\nGuido's address is %s" % ab['Guido'])

 

发现一个比较有趣现象，替换上面红色代码，得到同样的结果,

 

  for item in ab.items():
        print('Contact %s at %s' % item)           #遍历ab，返回类似于集合的对象,