python3笔记-字典

Posted 2020-10-25 月下独酌-婵儿

 

 

 1 # 创建字典
 2 d=dict(name=‘lily‘,age=18,phone=‘188011514000‘)
 3 print(d)
 4 # {‘name‘: ‘lily‘, ‘age‘: 18, ‘phone‘: ‘188011514000‘}
 5 
 6 # 通过key获取对应vlaue
 7 name =d[‘name‘]
 8 print(name)
 9 # lily
10 
11 # in，not in 判断key是否存在
12 if ‘name‘ in d:
13     print(‘name is exist‘)
14 else:
15     print(‘no‘)
16 
17 # 获取字典所有的key
18 keys = d.keys()
19 print(keys)
20 # dict_keys([‘name‘, ‘age‘, ‘phone‘])
21 
22 # dict.values() 返回一个包含字典所有value的列表
23 vlaue = d.values()
24 print(vlaue)
25 # dict_values([‘lily‘, 18, ‘188011514000‘])
26 
27 # dict.items()返回一个包含所有（键，值）元组的列表
28 keyandvlaue = d.items()
29 print(keyandvlaue)
30 # dict_items([(‘name‘, ‘lily‘), (‘age‘, 18), (‘phone‘, ‘188011514000‘)])
31 
32 # dict.fromkeys(seq, val=None) 创建并返回一个新字典，以seq中的元素做该字典的键，val做该字典中所有键对应的初始值（默认为None）
33 lk =[‘xiao‘,‘da‘,‘hong‘]
34 dic = dict.fromkeys(lk)
35 print(dic)
36 # {‘xiao‘: None, ‘da‘: None, ‘hong‘: None}
37 
38 
39 a = lambda x:x+1
40 print (a(3))