Swift Struct And Class Playground

SwiftStructAndClass.swift

//: Playground - noun: a place where people can play

import UIKit

//1.结构体类型的定义
struct MyPoint {
    var x: Float = 0
    var y: Float = 0
    
    mutating func setMyPoint(tempX: Float, tempY: Float) {
        x = tempX
        y = tempY
    }
    
    func display() {
        print("(\(x), \(y))")
    }
}

//2.结构体类型变量的声明以及结构体函数的使用
var myPoint = MyPoint()
myPoint.display()

myPoint.setMyPoint(2.3, tempY: 123.124)


//1. 类的创建与构造器
class YourPoint {
    var x: Float = 0
    var y: Float = 0
    
    init(x:Float = 1, y:Float = 2){
        self.x = x
        self.y = y
    }
    
    func setYourPoint(tempX: Float, tempY: Float) {
        x = tempX
        y = tempY
    }
    
    func display() {
        print("(\(x), \(y))")
    }
}

var yourPoint = YourPoint()
yourPoint.x
yourPoint.y

var hisPoint = YourPoint(x:123.213, y:2314)


//2.对象的赋值与比较
var a = YourPoint(x: 10, y: 20)
var b = a


b.x
b.y

a.x = 100
a.y = 200

b.x
b.y

//3.属性的懒加载（lazy）
class MyCycle {
    var r: Float = 0
    lazy var cyclePoint = YourPoint(x: 5, y: 6)
}

var myCycle = MyCycle()
myCycle.cyclePoint

//4. 计算属性（Count Property）
class Money {
    var CNY: Double = 0
    var USD: Double {
        get {
            return self.CNY / 6.4581
        }
        set(usd) {
            self.CNY = usd * 6.4581
        }
    }
}

var money = Money()
money.USD = 10//CNY马上被计算出来
money.CNY
money.CNY = 64.581//USD需要调用get方法才能获取
money.USD


//6. 实例方法与类方法
class MyTestClass {
    func objectMethod() {
        print("我是实例方法，需要实例化后才能调用")
    }
    
    class func classMethod() {
        print("我是类方法，无需实例化就可以调用")
    }
}

MyTestClass.classMethod()
var myTestClass = MyTestClass()
myTestClass.objectMethod()