Javascript add dynamic function to an object

Question

Is there any way to add a function to an object without knowing it's name in advance?

I do something like:

var $functionName = "sayHello"; 

object."$functionName" = function (args) {
     // Do stuff 
} 

/// Later

object.sayHello ("Henry");

Answer 1

Yes:

var functionName = "sayHello";

anObject[functionName] = function (args) {
    // ...
}

Note that a.b is syntactic sugar for a["b"] -- they mean exactly the same thing.

Answer 2

You could use the array format for this:

object[$functionName] = function () {}