//字典的定義
var dict1 = ["swift":"雨燕","python":"大蟒","java":"爪哇國"]
//問題：dict1 長度是多少兴喂？ 3
var dict2:[String:String] = ["swift":"雨燕","python":"大蟒","java":"爪哇國"]
var dict3:Dictionary<String,String> = ["swift":"雨燕","python":"大蟒","java":"爪哇國"]
//空字典的定義
var empty1:[Int:String] = [:]
var empty2:Dictionary<String,String> = [:]
var empty3 = [String:String]()
//基本操作：長度，判斷是否為空再菊，取值
print(dict1.count)
print(dict1.isEmpty)
print(dict1["java"]!)//返回值是一個可選型，通過!進行解包 //字典的特點:1)無序 2)鍵不能重復(fù)
//字典的特點：1無序 2鍵不能重復(fù)
let d1 = [1:"a",2:"b",3:"d"]
let d2 = [2:"b",1:"a",3:"d"]
print(d1==d2)//true //let d3 = [2:"b",1:"a",3:"d",3:"e"] --報錯
//遍歷-key,value,key-value
for key in dict1.keys{
print(key)
}
for value in dict1.values{
print(value)
}
for (key,value) in dict1{
print(key,value)
}
//增刪改查
//如果這個Key當(dāng)前沒有弄砍，添加操作披坏；如果當(dāng)前這個Key存在，修改操作
//改
var user=["name":"miao","pwd":"123","job":"coder"]
user["job"] = "teacher"
print(user)
//user.updateValue("456",forKey:"pwd")//更新值
var oldPwd = user.updateValue("456",forKey:"pwd")!//返回原來value的值
if oldPwd == user["pwd"]{
print("修改后的密碼與修改前一樣馏慨，可能會導(dǎo)致安全問題埂淮！")
}
print(user)
//添加
user["email"] = "56429@qq.com"
user.updateValue("chuzhou",forKey:"location")
print(user)
//刪除
user.removeValue(forKey:"location")
user["email"] = nil //null
print(user)
