字典
# 字典 # info = { # "k1" : "v1", #键值对 # "k2" : "v2", # } ##字典的Value可以是任何值 info = { "k1":18, "k2":True, "k3":[ 11, 22, [1,2], "233" ], } print(info)
#列表、字典不能成为字典的key
#字典是无序的,故不能切片查找
#索引方式查找指定元素 v = info["k3"][0] print(v)
#字典支持删除 del info["k3"][2][0] print(info)
#for循环 for item in info: print(item) for item in info.keys(): #键值 print(item) for item in info.values(): #Value值 print(item)
for item in info:
print(item,info[item]) for item in info.items(): #键对值 print(item)
di = { "k1":"ab", } #根据序列创建字典,并指定统一的值 #def fromkeys(*args, **kwargs): v = dict.fromkeys([1,2,3],"abc") print(v)
#根据key获取值,若key不存在,则指定值22222,默认为none #def get(self, k, d=None): v = di.get("adaa",22222) print(v)
di = { "k1":"ab", "k2":"bd", } def pop(self, k, d=None): v = di.pop("k1",90) print(di,v) #指定key,删除,并获取值 #def popitem(self): v = di.popitem() #随机删除,并获取值 print(di,v)
di = { "k1":"ab", "k2":"bd", } #def setdefault(self, k, d=None): v = di.setdefault("k12",66) #设置值,已经存在,不设置,获取当前key对应值;若不存在,设置, print(di,v)
di = { "k1":"ab", "k2":"bd", } #两种调用方式,更新 #def update(self, E=None, **F): di.update({'k1': '11111','k3':123}) di.update(k1=123,k3=345,k5="sdwq") print(di)
keys()
values()
item()
get()
update()
比较常用