?

document.getElementById('msgdiv').style.left=getPosLeft(a)+25;

?? document.getElementById('msgdiv').style.top=getPosTop(a)+15

?

a为要取到坐标的对象

?

function getPosLeft(obj)
{
??? var l = obj.offsetLeft;
??? while(obj = obj.offsetParent)
??? {
??????? l += obj.offsetLeft;
??? }
??? return l;
}

?

?

function getPosTop(obj)
{
??? var l = obj.offsetTop;
??? while(obj = obj.offsetParent)
??? {
??????? l += obj.offsetTop;
??? }
??? return l;
}