IE 下的朦版效果

    loadingTipDiv.innerHTML = "<div style='background-color:silver;position:absolute;left:0px;top:0px;width:100%;height:100%;filter:progid:DXImageTransform.Microsoft.Alpha(opacity=50);opacity:0.5;'></div>"
      + "<div class='loadingTip' style='position:absolute;'><TABLE cellSpacing=\"2\"><TR><TD><IMG src=\"" + 
      + "/images/loading.gif\"></TD>" + "<TD style=\"white-space: nowrap\">" 
      + text + "</TD></TR></TABLE></div>";
    document.body.appendChild(loadingTipDiv);
  };