window.dialog传值

================父窗口代码========
<HEAD>
<HTML>
<HEAD>
<TITLE>test2.htm</TITLE>
<SCRIPT>
var sUserName="";              

// 弹出窗口
function fnCallDialog()                                             
{
 showModalDialog("test3.html", window, "dialogWidth:300px;dialogHeight:300px");
}

// 根据子窗口的值，更新父窗口的页面内容
function fnUpdate()
{
  oName.innerText = sUserName;
}
</SCRIPT>
</HEAD>
<BODY>
<P>Hello World <input type="TEXT" readonly ID="oName" value="JACK"></input></P> 
<INPUT TYPE="button" VALUE="Show Dialog" onclick="fnCallDialog()">
</BODY>
</HTML>


=============子窗口代码=============
<HTML>
<HEAD>
<TITLE>test3.htm</TITLE>
<SCRIPT>

function fnGetInfo()
{
  // dialogArguments是接口参数，表示父窗口对象，不能变！
  var sData = dialogArguments;
  // 把本页面输入的值赋给父窗口的属性
  sData.sUserName = oEnterName.value;
  // 调用父窗口函数
  sData.fnUpdate();
}

</SCRIPT>
</HEAD>
<BODY>
Enter your Name
<INPUT ID=oEnterName><BR><BR>
<INPUT VALUE="OK!!!" TYPE=button onclick="fnGetInfo();window.close();">
</BODY>
</HTML> 


===========第二个问题的代码======
<HEAD>
<HTML>
<HEAD>
<TITLE>test2.htm</TITLE>
<SCRIPT>

function getOptionValue(sObj) {
    mytext.value = sObj.value;
}

</SCRIPT>
</HEAD>
<BODY>

<SELECT NAME="Cats" SIZE="1" onchange="getOptionValue(this)">
<OPTION VALUE="1">Hello
<OPTION VALUE="2">World
<OPTION VALUE="3">Jack
</SELECT>
    
<input type="text" id="mytext" value="1"/>
</BODY>
</HTML>