Swift中級學習 3 字典DIctionary

存儲 鍵-值 數據對的無序數據集

var dict: [String:String] = ["1":"ss","2":"dd"]

var dict1: Dictionary<</span>String,String> = ["2":"dd","1":"ss"]

print(dict["1"]) //可選性 Optional

dict == dict1

dict.count

dict.isEmpty

Array(dict.keys)

Array(dict.values)

//字典遍歷

for key in dict.keys{}

for value in dict.values{}

for (key,value) in dict{}

//空字典

var dictt1: [Int:String] = [:]

var dictt2: Dictionary<</span>Int,String> = [:]

var dictt3 = [Int:String]()

var dictt4 = Dictionary<</span>Int,String>()

//改

var user = ["name":"yang","password":"fangfang","sex":"wumen","age":"22"]

user["name"] = "yangyang"

user.updateValue("yang", forKey: "name") //返回舊的值

let new = user.updateValue("yang", forKey: "name")

//增

user["email"] = "[email protected]"  //不存在的

user.updateValue("15711111111", forKey: "phone")

user

//刪

user["phone"] = nil

user

user.removeValueForKey("email")

user.removeAll()