模式窗口
1.弹出窗口，底层页面不可以点
   window.showModalDialog(URL,dialogArgments.features) 打开一个新窗口
2.弹出窗口，底层页面还可以点
  <script language=javascript>window.showModelessDialog ('find_Job/recruit_day.aspx','','status:false;dialogWidth:1002px;dialogHeight:800px;edge:Raised; enter: Yes; help: No; resizable: Yes; status: No')</script>