Get function parameter names for interface purposes

Question

can anyone help me on how to retrieve function parameter names? For example:

var A = function(a, b, c) {};

I need to get the parameter name

Answer 1

I doubt that there is any decent way to this, in javascript parameter values can be of different type when passed, the types doesn't matter but the order thus.

This might not be the answer that you are looking for but this could help at least.

function test(a,b,c,d) {

}

//this will give us the number of parameters defined in the a function.
confirm(test.length); 

To really know the names you can parse the function definition

  var str = window['test'].toString();
   //str will be "function test(a,b,c,d){}"

Below is a simple parsing test I made:

function test(a,b,c,d)
{

}

var b = function(x,y,  z){};
alert(getFnParamNames(b).join(","));
alert(getFnParamNames(test).join(","));

function getFnParamNames(fn){
    var fstr = fn.toString();
    return fstr.match(/\(.*?\)/)[0].replace(/[()]/gi,'').replace(/\s/gi,'').split(',');
}