부모창에서 사용자가 이동할때 팝업창 자동으로 닫히게 하기

<script type="text/javascript" >
var childWindow1;

//보고서팝업
function openRpt(frm){
 childWindow1 = window.open("","srchRpt","scrollbars=no,toolbar=no,resizable=no,width=420,height=510,left=0,top=0");
 //alert(childWindow1);
 frm.target = "srchRpt";
 frm.action = "/fs/dis/com/DISRptSrch.jsp"
 frm.method="post";
 frm.submit();
 childWindow1.focus();
}

/*-- 팝업 닫기--*/
function windowClose() {
 try {
  if(childWindow1) childWindow1.close();
 }
 catch(e) {}

 try {
  if(childWindow2) childWindow2.close();
 }
 catch(e) {}
}
window.attachEvent("onunload",windowClose);