//改变图片大小
function resizepic(thispic)
{
if(thispic.width>550) thispic.width=550;
}
//无级缩放图片大小
function bbimg(o)
{
  var zoom=parseInt(o.style.zoom, 10)||100;
  zoom+=event.wheelDelta/12;
  if (zoom>0) o.style.zoom=zoom+'%';
  return false;
}