确定弹出窗口是否被拦截

<script language="javascript">
 var canopen=window.open();
 if(typeof(canopen)!="undefined" && canopen.open && !canopen.close)
 {
  alert("窗口已经被拦截,请在你的IE工具栏上的上网帮助工具中选择不要拦截本站点!");
  window.location="index.htm";
 }
 else
  window.open("index.htm","","fullscreen=1")
</script>