How to get the position of a control using Javascript?

Here is a handy functions to get the posisiton of a control using Javascript:

Usage:

alert(getElementPosition('txtName').top + ' ' + getElementPosition('txtName').left);

Function:

 function getElementPosition(elemID) {
             var offsetTrail = document.getElementById(elemID);
             var offsetLeft = 0;
             var offsetTop = 0;
             while (offsetTrail) {
                 offsetLeft += offsetTrail.offsetLeft;
                 offsetTop += offsetTrail.offsetTop;
                 offsetTrail = offsetTrail.offsetParent;
             }
             return { left: offsetLeft, top: offsetTop };
         }

We can get the current scroll position of the document using:

var scrolly = typeof window.pageYOffset != 'undefined' ? window.pageYOffset : document.documentElement.scrollTop;
var scrollx = typeof window.pageXOffset != 'undefined' ? window.pageXOffset : document.documentElement.scrollLeft;

Hope this helps you...