// JScript 文件
function getElementPos(elementId) {

	var ua = navigator.userAgent.toLowerCase();
	var isOpera = (ua.indexOf('opera') != -1);
	var isIE = (ua.indexOf('msie') != -1 && !isOpera); // not opera spoof

	var el;
	switch(typeof(elementId))
	{
	    case "string":
	        el = document.getElementById(elementId);
	        break;
	    case "object":
	        el = elementId; 
	        break;     
	}

	if(el.parentNode === null || el.style.display == 'none') 
	{
		return false;
	}

	var parent = null;
	var pos = [];
	var box;

	if(el.getBoundingClientRect)	//IE
	{
		box = el.getBoundingClientRect();
		var scrollTop = Math.max(document.documentElement.scrollTop, document.body.scrollTop);
		var scrollLeft = Math.max(document.documentElement.scrollLeft, document.body.scrollLeft);

		return {x:box.left + scrollLeft, y:box.top + scrollTop};
	}
	else if(document.getBoxObjectFor)	// gecko
	{
		box = document.getBoxObjectFor(el);
		   
		var borderLeft = (el.style.borderLeftWidth)?parseInt(el.style.borderLeftWidth):0;
		var borderTop = (el.style.borderTopWidth)?parseInt(el.style.borderTopWidth):0;

		pos = [box.x - borderLeft, box.y - borderTop];
	}
	else	// safari & opera
	{
		pos = [el.offsetLeft, el.offsetTop];
		parent = el.offsetParent;
		if (parent != el) {
			while (parent) {
				pos[0] += parent.offsetLeft;
				pos[1] += parent.offsetTop;
				parent = parent.offsetParent;
			}
		}
		if (ua.indexOf('opera') != -1 
			|| ( ua.indexOf('safari') != -1 && el.style.position == 'absolute' )) 
		{
				pos[0] -= document.body.offsetLeft;
				pos[1] -= document.body.offsetTop;
		} 
	}
		
	if (el.parentNode) { parent = el.parentNode; }
	else { parent = null; }
  
	while (parent && parent.tagName != 'BODY' && parent.tagName != 'HTML') 
	{ // account for any scrolled ancestors
		pos[0] -= parent.scrollLeft;
		pos[1] -= parent.scrollTop;
  
		if (parent.parentNode) { parent = parent.parentNode; } 
		else { parent = null; }
	}
	return {x:pos[0], y:pos[1]};
}