字典

左手的ㄟ右手 2022-03-30 13:20 263阅读 0赞

字典常用方法

![1184802-20180204162939014-1636041399.png][]

字典的表示方法：
    
    info_dic={
        'name':'haiyna','age':18,'sex':'female'}
    # 常用操作：
    #
    1.存/取
    info_dic={
        'name':'egon','age':18,'sex':'male'}
      print(info_dic['name11111111'])#找不到则报错了
      print(info_dic.get('name',None))
      print(info_dic.get('name222222',None))#get方法找不到不报错，可以自己设定默认值
    
    #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
    # print(info_dic.pop('nam123123123123123123e',None))
    # print(info_dic)
    
    # print(info_dic.popitem())
    # print(info_dic)
    
    # info_dic['level']=10
    # print(info_dic)
    
    #
    # 　　　　删除
    info_dic={
        'name':'egon','age':18,'sex':'male'}
    # info_dic.pop()
    # info_dic.popitem()
    
    # del info_dic['name']
    
    
    #
    # 　　　　键s，值s，键值对
    info_dic={
        'name':'egon','age':18,'sex':'male'}
    # print(info_dic.keys())
    # print(info_dic.values())
    # print(info_dic.items())
    
    # for k in info_dic:
    #     # print(k,info_dic[k])
    #     print(k)
    
    # print('========>')
    # for k in info_dic.keys():
    #     print(k)
    
    # for val in info_dic.values():
    #     print(val)
    
    # for k,v in info_dic.items(): #k,v=('name', 'egon')
    #     print(k,v)
    
    
    
    # 　　　　长度
    # info_dic={'name':'egon','age':18,'sex':'male'}
    # print(len(info_dic))
    #
    # 　　　　循环
    #
    # 　　　　包含in
    
    # info_dic={'name':'egon','age':18,'sex':'male'}
    # print('name' in info_dic)
    # print('name' in info_dic.keys())
    # print('egon' in info_dic.values())
    # print(('name','egon') in info_dic.items())
    
    
    
    #掌握
    info_dic={
        'name':'egon','age':18,'sex':'male'}
    # info_dic.update({'a':1,'name':'Egon'})
    # print(info_dic)
    
    # info_dic['hobbies']=[]
    # info_dic['hobbies'].append('study')
    # info_dic['hobbies'].append('read')
    # print(info_dic)
    
    #setdefault:key不存在则设置默认值，并且放回值默认值
    #key存在则不设置默认，并且返回已经有的值
    
    # info_dic.setdefault('hobbies',[1,2])
    # print(info_dic)
    # info_dic.setdefault('hobbies',[1,2,3,4,5])
    # print(info_dic)
    
    # info_dic={'name':'haiyan','age':18,'sex':'male'}
    
    # {'name':'egon','age':18,'sex':'male','hobbies':['study']}
    # info_dic.setdefault('hobbies',[]).append('study')
    
    # {'name':'egon','age':18,'sex':'male','hobbies':['study','read']}
    # info_dic.setdefault('hobbies',[]).append('read')
    
    # {'name':'egon','age':18,'sex':'male','hobbies':['study','read','sleep']}
    # info_dic.setdefault('hobbies',[]).append('sleep')
    # l=info_dic.setdefault('hobbies',[])
    # print(l,id(l))
    # print(id(info_dic['hobbies']))
    
    # print(info_dic)
    
    
    
    #了解
    # d=info_dic.copy()
    # print(d)
    # info_dic.clear()
    # print(info_dic)
    
    
    # d=info_dic.fromkeys(('name','age','sex'),None)
    # print(d)
    # d1=dict.fromkeys(('name','age','sex'),None)
    # d2=dict.fromkeys(('name','age','sex'),('egon',18,'male'))
    # print(d1)
    # print(d2)
    
    
    
    
    # info=dict(name='haiyan',age=18,sex='male')
    # print(info)
    
    #
    # info=dict([('name','haiyan'),('age',18)])
    # print(info)

[1184802-20180204162939014-1636041399.png]: /images/20220330/33832150808e4ba79abd64958546c6fd.png