在Swift中，如何获得变量的完全限定名称？

Question

Consider this code in an app called 'MyApp'...

class Foo{
    class Laa{
        static let laaVar = "I am laaVar"
    }
}

I know I can get the fully-qualified name of Laa , like so...

let laaName = String(reflecting: Foo.Laa.self)
// Returns 'MyApp.Foo.Laa'

but how can I get the fully-qualified name of laaVar (eg "MyApp.Foo.Laa.laaVar")?

Is that even possible?

Bonus Question

Given the above code, and a variable containing the string "MyApp.Foo.Laa.laaVar", how can I get the value "I am laaVar"?

I'm guessing the answer to both has something to do with reflection/mirroring.

Answer 1

I think I found a solution for your question. You might use the Objective-c runtime, especially the function class_copyPropertyList which describes the properties declared by a class. Example:

import Foundation

class Foo {
    class Laa: NSObject {
        @objc static let laaName = "I am laaVar"
    }
}

var count: CUnsignedInt = 0
let methods = class_copyPropertyList(object_getClass(Foo.Laa.self), &count)!
for i in 0 ..< count {
    let selector = property_getName(methods.advanced(by: Int(i)).pointee)
    if let key = String(cString: selector, encoding: .utf8) {
        let res = Foo.Laa.value(forKey: key)
        print("name: \(key), value: \(res ?? "")")
    }
}

the result is:

name: laaName, value: I am laaVar