In JavaScript, how do I access a function on an object using a string argument?

Question

So, for example, I have one function someObject.doSomething() & another function someFunction(whatObject, whatFunction) . I want to be able to use someFunction like this: someFunction('someObject', 'doSomething') and have it call someObject.doSomething() .

Basically what I want to do is pass strings to a function that can then use those strings to call other functions.

Answer 1

So you have two objects, object A & B.

A.doSomething = function(){...}
B.doSomethingElse = function(){...}

Now for A to doSomethingElse, you can use call as so:

B.doSomethingElse.call(A);

This changes the this of doSomethingElse to the scope of A, which makes so the function doSomethingElse is applied on A.

Answer 2

Use this:

 function doIt(obj, fn){ (new Function(obj+"."+fn+"()"))(); }; var A = {b:function(){ alert("test"); }} doIt("A", "b"); 

Answer 3

You could execute a string as code with eval.

function execute(objectName, objectFunction){
    eval(objectName + "." + objectFunction+"();");
}

execute("anotherObject", "doSomethingElse");

But caution with this command, this might throw a exception if either the object or the function does not exist.