python--Dictionary

#字典的速度很快, the more the list element takes more slowly
names={' Nicole ': [18, ' female ', 9999, ' Shanxi ']
,
' haha ': {' age ': +, ' sex ': ' Female '}
}
#查询
#print (names[' QQ ') #如果key不存在会报错
#print (Names.get (' nn ')) #如果key不存在, return None
#增, modify
# names[' Smile ']=[20, ' male ', ' Haidian District '] #如果已经存在则是修改
# Print (names)
#删除
# del names[' haha '] #如果不存在则报错
# Print (names)
# Names.pop (' Nicole ') #如果不存在则报错, Python is officially recommended to use this method
# Names.popitem () #随机删除一个key

#内置方法
Print (Names.keys ()) #返回这个字典所有key的值
Print (Names.values ()) #返回这个字典所有value的值
Names.setdefault (' hehe ', [' Female ', 28,999]) #增加值, if this key of set exists, then the original value is not moved, if it does not exist, it will be added
newnames={' Look ': [18, ' female ', 9999, ' Shanxi ']
,
' Slowly ': {' age ': ' Sex ': ' Female '}
}
Names.update ((newnames)) #扩展字典, update newnames to names
#names. Has_key (' key ') #判断有没有某个key值, there is this method in Python2, Python3 does not have
Print (' hehe ' in names) #判断字典中有没有这个key
# for k in Names:
# print (k) #打印key值
Names.items () #把字典转成一个list
# for K, V in Names.items ():
# print (k,v) #获取字典中key和value对应的值
#字典转换成list之后循环效率会变低, high-efficiency methods can
For k in Names: #这种方式很高效
Print (K,names[k]) #获取字典中key和value对应的值

python--Dictionary