Swift 函数

//函数 函数名 参数名:参数类型   返回值类型

 funcsayHello(name: String) ->String{

   return"my name is " + ( name?? "Guest" )//聚合运算符

}

var nickname: String? = nil

//sayHello(nickname)

func printHello(){ //无参 无返回

}

func printHello1() ->(){ //无参 无返回

}

func printHello2() -> Void{ //无参 无返回

}

func returnYuanZu (num :Int ,_ num2:Int) ->(max :Int ,min : Int){ //返回元组

                  // _ 参数名省略

   let maxNum = 10 +num

   let minNum = 0 +num

   return(maxNum ,minNum)

}

returnYuanZu(2,0)

returnYuanZu(2,0).max

returnYuanZu(2,0).min

func getString(string1 : String,string2 :String) ->String{

   returnstring1 + string2

}

getString("我的",string2: "电脑")

func getStringing2(string1 : String,getString string2 :String = "ssss") ->String{

   returnstring1 + string2

}

getStringing2("小米")

 

getStringing2("小米",getString: "hello")