字典

字典常用方法

  1 字典的表示方法:
  2 
  3 info_dic={'name':'haiyna','age':18,'sex':'female'}
  4 # 常用操作:
  5 #
  6 1.存/取
  7 info_dic={'name':'egon','age':18,'sex':'male'}
  8   print(info_dic['name11111111'])#找不到则报错了
  9   print(info_dic.get('name',None))
 10   print(info_dic.get('name222222',None))#get方法找不到不报错,可以自己设定默认值
 11 
 12 #pop:key存在则弹出值,不存在则返回默认值,如果没有默认值则报错
 13 # print(info_dic.pop('nam123123123123123123e',None))
 14 # print(info_dic)
 15 
 16 # print(info_dic.popitem())
 17 # print(info_dic)
 18 
 19 # info_dic['level']=10
 20 # print(info_dic)
 21 
 22 #
 23 #     删除
 24 info_dic={'name':'egon','age':18,'sex':'male'}
 25 # info_dic.pop()
 26 # info_dic.popitem()
 27 
 28 # del info_dic['name']
 29 
 30 
 31 #
 32 #     键s,值s,键值对
 33 info_dic={'name':'egon','age':18,'sex':'male'}
 34 # print(info_dic.keys())
 35 # print(info_dic.values())
 36 # print(info_dic.items())
 37 
 38 # for k in info_dic:
 39 #     # print(k,info_dic[k])
 40 #     print(k)
 41 
 42 # print('========>')
 43 # for k in info_dic.keys():
 44 #     print(k)
 45 
 46 # for val in info_dic.values():
 47 #     print(val)
 48 
 49 # for k,v in info_dic.items(): #k,v=('name', 'egon')
 50 #     print(k,v)
 51 
 52 
 53 
 54 #     长度
 55 # info_dic={'name':'egon','age':18,'sex':'male'}
 56 # print(len(info_dic))
 57 #
 58 #     循环
 59 #
 60 #     包含in
 61 
 62 # info_dic={'name':'egon','age':18,'sex':'male'}
 63 # print('name' in info_dic)
 64 # print('name' in info_dic.keys())
 65 # print('egon' in info_dic.values())
 66 # print(('name','egon') in info_dic.items())
 67 
 68 
 69 
 70 #掌握
 71 info_dic={'name':'egon','age':18,'sex':'male'}
 72 # info_dic.update({'a':1,'name':'Egon'})
 73 # print(info_dic)
 74 
 75 # info_dic['hobbies']=[]
 76 # info_dic['hobbies'].append('study')
 77 # info_dic['hobbies'].append('read')
 78 # print(info_dic)
 79 
 80 #setdefault:key不存在则设置默认值,并且放回值默认值
 81 #key存在则不设置默认,并且返回已经有的值
 82 
 83 # info_dic.setdefault('hobbies',[1,2])
 84 # print(info_dic)
 85 # info_dic.setdefault('hobbies',[1,2,3,4,5])
 86 # print(info_dic)
 87 
 88 # info_dic={'name':'haiyan','age':18,'sex':'male'}
 89 
 90 # {'name':'egon','age':18,'sex':'male','hobbies':['study']}
 91 # info_dic.setdefault('hobbies',[]).append('study')
 92 
 93 # {'name':'egon','age':18,'sex':'male','hobbies':['study','read']}
 94 # info_dic.setdefault('hobbies',[]).append('read')
 95 
 96 # {'name':'egon','age':18,'sex':'male','hobbies':['study','read','sleep']}
 97 # info_dic.setdefault('hobbies',[]).append('sleep')
 98 # l=info_dic.setdefault('hobbies',[])
 99 # print(l,id(l))
100 # print(id(info_dic['hobbies']))
101 
102 # print(info_dic)
103 
104 
105 
106 #了解
107 # d=info_dic.copy()
108 # print(d)
109 # info_dic.clear()
110 # print(info_dic)
111 
112 
113 # d=info_dic.fromkeys(('name','age','sex'),None)
114 # print(d)
115 # d1=dict.fromkeys(('name','age','sex'),None)
116 # d2=dict.fromkeys(('name','age','sex'),('egon',18,'male'))
117 # print(d1)
118 # print(d2)
119 
120 
121 
122 
123 # info=dict(name='haiyan',age=18,sex='male')
124 # print(info)
125 
126 #
127 # info=dict([('name','haiyan'),('age',18)])
128 # print(info)

 

 

 

 

归类 :  python相关

posted @ 2019-09-23 18:28  Py猫的故事  阅读(157)  评论(0编辑  收藏  举报
返回顶部