“静态变量"与“静态变量"之间的差异和“var"在斯威夫特 [英] Differences between "static var" and "var" in Swift

问题描述

Swift 中static var"和var"的主要区别是什么?有人可以用一个小例子向我解释这种差异吗?

What is the main difference between "static var" and "var" in Swift? Can someone explain this difference to me, possibly with a little example?

推荐答案

static var 属于类型本身而 var 属于实例(特定类型的特定值) 的类型.例如:

static var belongs to type itself while var belongs to instance (specific value that is of specific type) of type. For example:

struct Car {
    static var numberOfWheels = 4
    var plateNumber: String
}

Car.numberOfWheels = 3
let myCar = Car(plateNumber: "123456")

所有汽车都有相同数量的车轮.您可以在 Car 本身类型上更改它.

All cars has same amount of wheels. An you change it on type Car itself.

为了改变车牌号，你需要有Car的实例.例如，myCar.

In order to change plate number you need to have instance of Car. For example, myCar.

这篇关于“静态变量"与“静态变量"之间的差异和“var"在斯威夫特的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！