Python--字典基本操作

#!/usr/bin/env python
# -*- coding:utf-8 -*-
# Author:Huanglinsheng


# 字典的特性：
# dict是无序的
# key必须是唯一的,so 天生去重

info = {
    'stu1': "TengLan Wu",
    'stu2': "LongZe Luola",
    'stu3': "XiaoZe Maliya",
}
print(info.values())
print(info.keys())

#setdefault
info.setdefault("stu6","Alex")

#增加
info["stu4"] = "hls"

#修改
info["stu4"] = "hc"

#删除
info.pop("stu4")
del info["stu3"]
info.popitem()  #随机删除

#查找
# "stu1102" in info   #标准用法
# info.get("stu1102")  #获取
# info["stu1102"] #同上，但是看下面
# info["stu1105"]  #如果一个key不存在，就报错，get不会，不存在只返回None

#update
b = {1:2,3:4, "stu1102":"龙泽萝拉"}
info.update(b)

#items
# info.items()
# dict_items([('stu1102', '龙泽萝拉'), (1, 2), (3, 4), ('stu1103', 'XiaoZe Maliya'), ('stu1106', 'Alex')])

#循环dict
#方法1
for key in info:
    print(key,info[key])

#方法2
for k,v in info.items(): #会先把dict转成list,数据里大时莫用
    print(k,v)













#多级字典嵌套及操作
youlan = {
    "运维":{
        "hc":["帅气","威猛"],
        "hls":["菜鸡","挖坑王"]
    },
    "运营":{
        "hht":["靓仔","大佬"],
        "lm":["美女","可爱"]
    },
    "服务端":{
        "cyl":["大佬","牛逼"],
        "zcw":["美女","可爱"]
    }
}

youlan["运维"]["hc"][1] = youlan["运维"]["hc"][1] + "牛逼"
print(youlan["运维"]["hc"][1])
for k in youlan:
    print(k)

=======================经典案例==================================

#!/usr/bin/env python
# -*- coding:utf-8 -*-
# Author:Huanglinsheng

menu = {
    '北京':{
        '海淀':{
            '五道口':{
                'soho':{},
                '网易':{},
                'google':{}
                    }
                }
            },
    '山东':{},
}


exit_flag = False
current_layer = menu
print(menu)

layers = []

while not  exit_flag:
    for k in current_layer:
        print(k)
    choice = input(">>:").strip()
    if choice == "b":
        current_layer = layers[-1]
        print(current_layer)
        #print("change to laster", current_layer)
        layers.pop()
    elif choice not  in current_layer:continue
    else:
        layers.append(current_layer)
        print(layers)
        current_layer = current_layer[choice]
        print(current_layer)