showModalDialog子窗口怎样向父窗口传参数

Test.asp

<script language="JavaScript">
<!--
function ShowDialog(url, width, height, optValidate) {
 var arr = showModalDialog(url, window, "dialogWidth:" + width + "px;dialogHeight:" + height + "px;help:no;scroll:no;status:no");
}
//-->
</script>

<form method="post" name="myForm" action="">
<input type="text" name="face" id="face"> <input type="button" value="测  试" onClick="ShowDialog('test.html',450,200)">
</form>

Test.html

<img src="site/bbs/images/userface/Image1.gif" onClick="insertValue('xxxxdddxx')">
<script language="JavaScript">
<!--
function insertValue(strValue)
{
 dialogArguments.document.myForm.face.value = strValue;
}
//-->
</script>