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Código:
<html>
<head>
<title> New Document </title>
<script language="JavaScript">
<!--
function cambio(){
document.forms[0].texto.value = document.forms[0].box.options[document.forms[0].box.selectedIndex].value;
}
//-->
</script>
</head>
<body bgcolor="#FFFFFF">
<form method=post action="">
<select name="box" onChange='cambio();'>
<option value="Juan"> Juan
<option value="Pedro">Pedro
</select><br>
<input type="text" name="texto" disabled>
</form>
</body>
</html>
<hr noshade size=1><img src="http://www.gograph.com/Images-8712/ClipArt/cat03.gif" height="50" border=0 align="absmiddle"> <font size="2" face="verdana" color="#000000">
bet[/CODE]