2-11字典类型的详细方法

字典类型的详细方法

>>> #查找
...
>>> info = {‘stu1101‘: ‘TengLan Wu‘, ‘stu1102‘: ‘LongZe Luola‘, ‘stu1103‘: ‘Xiao
Ze Maliya‘,
...  ‘stu1104‘: ‘Alex‘}
>>> "stu1102" in info #标准用法
True
>>> info.get(‘stu1102‘) #获取
‘LongZe Luola‘
>>> info[‘stu1102‘] #同上，但是看下面
‘LongZe Luola‘
>>> info[‘stu1105‘] #如果一个key不存在，就报错，get不会，不存在只返回None
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
KeyError: ‘stu1105‘

>>> #删除
...
>>> info = {‘龙婷‘:[24,‘设计部‘,‘UI‘,23333],‘shanshan‘:[22,‘PR‘,‘designer‘,14556
],‘Alex‘:[30,‘开发部‘,‘engineer‘,2114]}
>>> info.pop(‘shanshan‘) #pop删除后 返回删除的值
[22, ‘PR‘, ‘designer‘, 14556]
>>> info
{‘龙婷‘: [24, ‘设计部‘, ‘UI‘, 23333], ‘Alex‘: [30, ‘开发部‘, ‘engineer‘, 2114]}
>>> info
{‘龙婷‘: [24, ‘设计部‘, ‘UI‘, 23333], ‘Alex‘: [30, ‘开发部‘, ‘engineer‘, 2114],
1: 2, 2: 2, 3: 2}
>>> info.popitem() #随机删
(3, 2)
>>> info.popitem()
(2, 2)
>>> info.popitem()
(1, 2)
>>> info
{‘龙婷‘: [24, ‘设计部‘, ‘UI‘, 23333], ‘Alex‘: [30, ‘开发部‘, ‘engineer‘, 2114],
‘!‘: ‘aaa‘}
>>> del info[‘!‘]
>>> info
{‘龙婷‘: [24, ‘设计部‘, ‘UI‘, 23333], ‘Alex‘: [30, ‘开发部‘, ‘engineer‘, 2114]}
>>>

查找：get() 、中括号

删除：pop() 　　popitem()　　del

多级字典的嵌套

其他方法

>>> info
{‘Alex‘: [23, ‘IT‘], ‘rain‘: [24, ‘HR‘], ‘jack‘: 22}
>>> info.keys() # 所有的key
dict_keys([‘Alex‘, ‘rain‘, ‘jack‘])

>>> info.values() #所有的value
dict_values([[23, ‘IT‘], [24, ‘HR‘], 22])

>>> info.items() #把key和value 合成元祖，把字典转成一个大列表
dict_items([(‘Alex‘, [23, ‘IT‘]), (‘rain‘, [24, ‘HR‘]), (‘jack‘, 22)])

>>> info1={‘TT‘:[11,‘qq‘]}
>>> info.update(info1)    #把两个字典合成一个 ,类似列表中的extend()
>>> info
{‘Alex‘: [23, ‘IT‘], ‘rain‘: [24, ‘HR‘], ‘jack‘: 22, ‘TT‘: [11, ‘qq‘]}
>>>

>>> info={‘Alex‘: [23, ‘IT‘], ‘rain‘: [24, ‘HR‘], ‘jack‘: 22, ‘TT‘: [11, ‘qq‘]}
>>> dic2 ={1:2,2:3,‘jack‘:[22,‘Jack Ma‘,‘Alibaba‘]}
>>> info.update(dic2)
>>> info
{‘Alex‘: [23, ‘IT‘], ‘rain‘: [24, ‘HR‘], ‘jack‘: [22, ‘Jack Ma‘, ‘Alibaba‘], ‘TT
‘: [11, ‘qq‘], 1: 2, 2: 3}
>>>#upadate 没有的就创建，有的就覆盖

>>> info
{‘Alex‘: [23, ‘IT‘], ‘rain‘: [24, ‘HR‘], ‘jack‘: [22, ‘Jack Ma‘, ‘Alibaba‘], ‘TT
‘: [11, ‘qq‘], 1: 2, 2: 3}
>>> info.setdefault(2,‘new2‘)
3
>>> info
{‘Alex‘: [23, ‘IT‘], ‘rain‘: [24, ‘HR‘], ‘jack‘: [22, ‘Jack Ma‘, ‘Alibaba‘], ‘TT
‘: [11, ‘qq‘], 1: 2, 2: 3}
>>> info.setdefault(‘test‘,‘new2‘)
‘new2‘
>>> info
{‘Alex‘: [23, ‘IT‘], ‘rain‘: [24, ‘HR‘], ‘jack‘: [22, ‘Jack Ma‘, ‘Alibaba‘], ‘TT
‘: [11, ‘qq‘], 1: 2, 2: 3, ‘test‘: ‘new2‘}

>>> info.fromkeys([‘A‘,‘B‘,‘C‘],‘Alex‘)
{‘A‘: ‘Alex‘, ‘B‘: ‘Alex‘, ‘C‘: ‘Alex‘}

字典的循环

>>> info.fromkeys([‘A‘,‘B‘,‘C‘],‘Alex‘)
{‘A‘: ‘Alex‘, ‘B‘: ‘Alex‘, ‘C‘: ‘Alex‘}

原文地址：https://www.cnblogs.com/echo-kid-coding/p/11200408.html