定義一個(gè)字典

{key1:value1,key2:value2}

info = {"name":"laowang","old":18}

添加元素

info = {"name":"laowang","old":18}
info["old"] = 18 #info = {"name":"laowang","old":18}

修改元素

info = {"name":"laowang","old":18}
info["old"] = 20 #{"name":"laowang","old":20}

刪除元素

info = {"name":"laowang","old":18}
del info["old"] #{"name":"laowang"}

查詢?cè)?/h3>

info = {"name":"laowang","old":18}
info.get("name") #laowang
info.get("qq") # 空
info["qq"] #拋出異常

常用屬性

len 鍵值對(duì)的個(gè)數(shù)

info = {"name":"laowang","old":18}
info.len() # 打印信息2

keys 字典中所有的鍵列表

info = {"name":"laowang","old":18}
info.keys() # 打印信息["name","old"]

values 字典中所有的值列表

info = {"name":"laowang","old":18}
info.values() # 打印信息["laowang",18]

items 字典中所有的鍵值元組列表

info = {"name":"laowang","old":18}
info.items() # 打印信息[("name","laowang"),("old",18)]

字典中的key不能是列表類型，可以是字符串、數(shù)字、元組