python字典遍历实例讲解

用ipython运行情况如下：

#新建字典
In [1]: name_cards = {\'name\':\'sunwukong\',\'QQ\':\'123124\',\'addr\':\'秦皇岛\'}

#生成key对象
In [2]: name_cards.keys()
Out[2]: dict_keys([\'name\', \'QQ\', \'addr\'])

#生成value对象
In [3]: name_cards.values()
Out[3]: dict_values([\'sunwukong\', \'123124\', \'秦皇岛\'])

##生成item对象
In [4]: name_cards.items()
Out[4]: dict_items([(\'name\', \'sunwukong\'), (\'QQ\', \'123124\'), (\'addr\', \'秦皇岛\')])

#python的解包
In [5]: a,b = (3,5)

In [6]: a
Out[6]: 3

In [7]: b
Out[7]: 5

#遍历key
In [8]: for key in name_cards.keys():
   ...:     print(key)
   ...:     
name
QQ
addr

#遍历value
In [9]: for value in name_cards.values():
   ...:     print(value)
   ...:     
sunwukong
123124
秦皇岛

#用解包的方法遍历key，value
In [10]: for key,value in name_cards.items():
    ...:     print(key,value)
    ...:     
name sunwukong
QQ 123124
addr 秦皇岛