文本框双重克隆
<html>
<head>
<title>双重输入文字</title>
<script language="javascript">
<!--
function doubleType(){
form1.txt2.value = form1.txt1.value;
setTimeout("doubleType()",500);
}
//-->
</script>
</head>
<body onLoad="doubleType()">
<form name="form1">
<input type="text" name="txt1">
<input type="text" name="txt2">
</form>
</body>
</html>
