快速传递元素​​作为变量

Question

In javascript I know i can something like the following:

var foo = '';

function changeVariable(variable, data){
  this[variable] = data;
}

changeVariable("foo", "bar");

Is there away I can do this in swift?

func toggleFadeIn (element: String, active: Bool)
{
    if(!active){
        self.element.alpha = 0;
        self.element.transform = CGAffineTransform(translationX: 0, y: 25)
    }

}

Answer 1

Javascript is a dynamic language that has the facilities of modifying objects in such a way at runtime.

Static languages (like Swift, Java, C#, and many others) require a reflection library to implement such behaviour. Unfortunately, Swift has a really limited reflection capability ( Mirror ) and doesn't have the ability to modify object/struct members by their String names, yet.

If you elaborate on what exactly you were trying to achieve with this, we would be better able to suggest solutions.

Answer 2

What you describe IS possible using KVO on NSObjects . It relies on Objective-C dynamic messaging, but it does work. Take a look a the function setValue:forKey: , as documented in Apple's Key Value Programming Guide .

Note that this is decidedly un-swiftlike, and not recommended.