python-day8-字典的内置方法

# info=['egon','male',18,180,75]
#
#
# info_dic={'name':'egon','age':18,'sex':'male'}  # 有对应关系

# 常用操作：优先掌握
#
# 　　　　存/取
info_dic={'name':'egon','age':18,'sex':'male'}
# # print(info_dic['name11111111'])
# print(info_dic.get('name',None))  # 找不到默认是None，但可以指定内容：'没有啊哥们'

#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())

# 　　　　循环

# for k in info_dic:    ## 推荐这种方法
#     print(k,info_dic[k])
#     print(k)

# for k in info_dic.keys():       #了解
#     print(k)

# for val in info_dic.values():  #了解
#     print(val)

# for k,v in info_dic.items(): #k,v=('name', 'egon')  #了解
#     print(k,v)

# 　　　　长度
# info_dic={'name':'egon','age':18,'sex':'male'}
# print(len(info_dic))
#

#
# 　　　　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'})    # 原字典没有的加入，原字典有的则更新
# 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':'egon','age':18,'sex':'male'}

# info_dic.setdefault('hobbies',[]).append('study')
# {'name':'egon','age':18,'sex':'male','hobbies':['study']}

# info_dic.setdefault('hobbies',[]).append('read')
# {'name':'egon','age':18,'sex':'male','hobbies':['study','read']}

# info_dic.setdefault('hobbies',[]).append('sleep')
# {'name':'egon','age':18,'sex':'male','hobbies':['study','read','sleep']}

# print(info_dic)

# l=info_dic.setdefault('hobbies',[])
# print(l,id(l))
# print(id(info_dic['hobbies']))

#了解
# d=info_dic.copy()
# print(d)
# info_dic.clear()
# print(info_dic)

#fromkeys         #用来快速产生字典
# d1=dict.fromkeys(('name','age','sex'),None)
# d2=dict.fromkeys(('name','age','sex'),('egon',18,'male'))
# print(d1)
# print(d2)

#产生字典
# info=dict(name='egon',age=18,sex='male')
# print(info)

#产生字典
# info=dict([('name','egon'),('age',18)])
# print(info)