在父窗口中得知 window.open()出的子窗口关闭事件的方法（定时器实现)

<HTML><BODY>
<P> </P>
<form name=fm_Info>
<input type=text name=txtValue>
</form>
<script language=javascript>
var timer
var winOpen
function IfWindowClosed() {
if (winOpen.closed == true) {        document.fm_Info.txtValue.value="child closed"
    window.clearInterval(timer)
    }
}
</script>
<input type=button name=btnOpen value=open>

<script language=javascript for=btnOpen event=onclick>
document.fm_Info.txtValue.value=""
    winOpen=window.open("child.htm","","toolbar=no, location=no, directories=no, status=no, menubar=no" )
    timer=window.setInterval("IfWindowClosed()",500);
</script>
</BODY></HTML>

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