如何在Swift中动态创建对属性的引用

Question

我怎么能在swift中完成这个。

let thing1 = whatever //instance property on class

let index = 1
var myThing = self["thing\(index)"] //does not work

Answer 1

如果你的课程符合NSObject，你可以使用：

class Obj : NSObject {
  var a1 = "Hi"
}

let obj = Obj()
let ctr = 1
println (obj.valueForKey("a\(ctr)"))

要列出可用的属性，您可以使用以下内容（来自另一个SO问题）：

var count : UInt32 = 0
let classToInspect = Obj.self
let properties : UnsafeMutablePointer <objc_property_t> = class_copyPropertyList(classToInspect, &count)
var propertyNames : [String] = []
let intCount = Int(count)
for var i = 0; i < intCount; i++ {
  let property : objc_property_t = properties[i]
  let propertyName = NSString(UTF8String: property_getName(property))!
  propertyNames.append(propertyName)
}
free(properties)
println(propertyNames)