有没有办法从空数组中获取数组元素的实例？ （我需要动态属性，因为我在 NSObject 中使用了一些KVC方法）
import Foundation $ b class BaseClass：NSObject { func myFunction（）{ doWork（）} } class Car：BaseClass { dynamic var id：Int = 0 } class Bus：BaseClass {动态var变量：Int = 0 } var cars = Array< Car>（）我需要的是从这个空数组中获取空Car对象的实例，例如：
var carFromArray = cars.instanceObject（）//将返回空Car对象我知道我可以使用：
var object = Array< Car> .Element（）但是这对我不起作用，因为我从函数参数获取数组，并且我不知道它是元素类。
我试图写我自己的ty PE会做到这一点，它的工作原理，但我不能标记为动态，因为它不能在Objective C中表示。我试图写入数组的扩展
扩展数组{ func instanceObject< T：BaseClass>（） - > T' { return T（）} }但是当我使用它，它有时会抛出错误致命错误：NSArray元素无法匹配Swift数组元素类型
Swift 3：获取一个空数组的元素类型： let cars = [Car]（ ）// [] let arrayType = type（of：cars）// Array< Car> .Type let carType = arrayType.Element.self // Car.Type String ：carType）//Car
Is there a way to get instance of Array element from the empty array? (I need dynamic properties because I use some KVC methods on NSObject)
import Foundation class BaseClass: NSObject { func myFunction() { doWork() } } class Car: BaseClass { dynamic var id: Int = 0 } class Bus: BaseClass { dynamic var seats: Int = 0 } var cars = Array<Car>()What I need is a vay to get instance of empty Car object from this empty array, for example like this:
var carFromArray = cars.instanceObject() // will return empty Car objectI know that I can use:
var object = Array<Car>.Element()but this doesn't work for me since I get array from function parameter and I don't know it's element class.
I have tried to write my own type that will do this, and it works, but then I cannot mark it as dynamic since it cannot be represented in Objective C. I tried to write extension of Array
extension Array { func instanceObject<T: BaseClass>() -> T? { return T() } }but when I use it, it sometimes throws error fatal error: NSArray element failed to match the Swift Array Element type
解决方案Swift 3: Get an empty array's element type:
let cars = [Car]() // [] let arrayType = type(of: cars) // Array<Car>.Type let carType = arrayType.Element.self // Car.Type String(describing: carType) // "Car"
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