学步园

 
<script language="JavaScript" type="text/javascript"> 
<!-- 
 
// 说明：用 Javascript 获取指定页面元素的位置 
// 整理：http://www.codebit.cn 
// 来源：YUI DOM 
 
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 = document.getElementById(elementId); 
 
    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]}; 
} 
 
//--> 
</script>