Swift元组

元组是多个值组合而成的复合值。元组中的值可以是任意类型，而且每一个元素的类型可以是不同的。

元组声明

//普通声明var point = (5,2)var httpResponse = (404, "Not Found")//定义类型声明var point2 : (Int,Int,Int) = (10,5,2)var httpResponse2 : (Int,String) = (200,"ok")

元组解包

var point = (5,2)var httpResponse = (404, "Not Found")let (x,y) = point// x = 5 , y = 2var (statuseCode, statuseMessage) = httpResponse// statuseCode = 404 , statuseMessage = "Not Found"//此时因为元组(x,y)是let 类型的，所以x和y的值不能改变；而(statuseCode, statuseMessage)是var类型的所以statuseCode和statuseMessage的值可以改变x = 10 //举报错statuseCode = 405//不报错

元组也可以如同数组一样，根据索引进行解包，所以从0开始

var point = (5,2)point.0 //值为5point.1 //值为2

元组也可以如同字典一样，给每个值赋一个key作为名字，根据名字解包

let point3 = (x:3,y:2)point3.0 //值为3point3.x //值为3let point4 : (x:Int,y:Int) = (5,10)point4.x //值为5point4.y //值为10

部分解包，不需要的值用 _ 表示，对元组进行部分解包

//部分解包let loginResult = (true, "LXY")let (isLoginSuccess,_) = loginResultif isLoginSuccess{}