Swift - Class 기본

import Foundation

class Engine{

    var name:String

    

    // 클래스 초기화 함수

    init(initName:String){

        self.name = initName

    }

    

    init(){

        self.name = "Normal Engine"

    }

    

    func startEngine(){

        print ("Start Engine!")

    }

    

    func stopEngine(){

        print("Stop Engine")

    }

}

var myEngine = Engine(initName:"8기통")

class Tire{

    let name:String

    

    init(initName:String){

        name = initName

    }

}

var myTire = Tire(initName: "신발보다 싼 타이어")

class Car{

    var engine:Engine

    var tire:Tire

    

    init(){

        engine = Engine(initName: "8기통 엔진!")

        tire = Tire(initName: "금호 타이어")

    }

    

    func Start() -> Bool{

        engine.startEngine()

        return true

    }

}

let car = Car()

car.engine.name

car.tire.name

let result = car.Start()

print(myEngine.name + " " + myTire.name)

class SuperEngine: Engine{

    var year:String     // 저장 형 Property

    

    var info:String{    // 연산 형 Property

        get {

            return name + year

        }

        set {

            let index = newValue.endIndex.advancedBy(-4)    // newValue 는 setter 의 인자로 들어오는 값을 담는 변수

            year = newValue.substringFromIndex(index)

            name = newValue.substringToIndex(index)

        }

    }

    

    override init() {

        year = "0000"

        super.init()

        name = "Super Engine"

//        super.name = "Super Engine"

//        self.name = "Super Engine"

    }

    

    func speedUp(){

        print("Speed Up!")

    }

}

car.engine = SuperEngine()

car.engine.name

// 타입 캐스팅

var superEngine = car.engine as! SuperEngine

superEngine.speedUp()

superEngine.info

superEngine.info = "Hyper Engine2016"

superEngine.info

superEngine.name

superEngine.year