Swift继承

//声明一个基类

class vehicle {

    var maxPassenger : Int = 0

    var manufacturer : String!

    

    func description() -> String {

        return "max passenger is (maxPassenger) and manufacturer is (manufacturer)"

    }

    

    init () {

        maxPassenger = 2

        manufacturer = "Designed By Weasley"

    }

}


//声明子类

class Bicycle : vehicle {

    var numberofWheels : Int = 2

    var maxSpeed : Double = 30

    

    override init() {

        super.init()

        maxPassenger = 2

    }

    

    override func description() -> String {

        //return "numberofWheels : (numberofWheels) maxPassenger : (maxPassenger) with maxSpeed : (maxSpeed) manufacturer is (manufacturer)"

        return super.description() + ";" + "numberofWheels : (numberofWheels) maxSpeed : (maxSpeed)"

    }

}



class LimitSpeedBicycle: Bicycle {

    override var maxSpeed : Double {

        get {

            return super.maxSpeed

        }

        set {

            super.maxSpeed = min(maxSpeed, 20)

        }

    }

}

var bicycle = Bicycle()

println(bicycle.description())


var limit = LimitSpeedBicycle()

limit.maxSpeed = 30

println(limit.maxSpeed)



class SpeedLevel: Bicycle {

    var level  = 1

    override var maxSpeed : Double{

        didSet{

            level = Int(maxSpeed / 10) + 1

        }

    }

    

    override func description() -> String {

        return super.description() + " level is (level)"

    }

}

var aBicycle = SpeedLevel()

aBicycle.maxSpeed = 40

println(aBicycle.description())


原文地址:https://www.cnblogs.com/mengfanrong/p/5094393.html