How can I determine a function's argument count at runtime in Flex 3?

Question

I want to pass an optional data parameter to some callbacks, but only to callbacks that support a single parameter; right now, I have a moderately-sized code base of callbacks that cannot accept a parameter at all. How can I check what parameters a Function object supports?

Answer 1

If your function is declared in a class use the function describeType it will return an XML you can parse and look at your function name with his arguments

Answer 2

The arguments array is an array of all the parameters passed into a function. Maybe that is what you are looking for?

function traceArgArray(x:int):void
{
    for (var i:uint = 0; i < arguments.length; i++)
    {
        trace(arguments[i]);
    }
}

Example taken from livedocs.adobe.com