javascript:window.showModalDialog缓存问题

window.showModalDialog会有缓存，导致第二次不进入pageload，解决方法：跟一个随机的参数：

          var time =new Date();
          var iWidth=840;
          var iHeight=350;
          var retval = window.showModalDialog('CustomerChargeDetail.aspx?HouseID=' + HouseParam+"&time="+time,'son','dialogwidth:'+iWidth+'px;dialogheight:'+iHeight+'px;help:no;status:no;scroll:directories:no;scrollbars:no;Resizable=no;')