muchas gracias ha quedado exelente, aca dejo el codigo
Código HTML:
<html>
<head>
<script type="text/javascript">
function insertar() {
obj=document.getElementById('sel1');
if (obj.selectedIndex==-1) return;
valor=obj.value;
txt=obj.options[obj.selectedIndex].text;
obj.options[obj.selectedIndex]=null;
obj2=document.getElementById('sel2');
opc = new Option(txt,valor);
eval(obj2.options[obj2.options.length]=opc);
}
function eliminar(){
obj2=document.getElementById('sel2');
if (obj2.selectedIndex==-1) return;
valor=obj2.value;
txt=obj2.options[obj2.selectedIndex].text;
obj2.options[obj2.selectedIndex]=null;
obj1=document.getElementById('sel1');
opc = new Option(txt,valor);
eval(obj1.options[obj1.options.length]=opc);
}
function vaciar() {
obj2 = document.getElementById('sel2');
num = obj2.options.length;
for (i=num-1; i>=0; i--) {
txt=obj2.options[i].text;
valor=obj2.options[i].value;
obj2.options[i]=null;
obj=document.getElementById('sel1');
opc = new Option(txt,valor);
eval(obj.options[obj.options.length]=opc);
}
}
</script>
</head>
<body>
<?php
$myTextArea=$_POST['myTextArea'];
echo "<hr noshade>";
echo $myTextArea;
$ok=1;
?>
<hr noshade><br><br><form action="go.php" method="post">
<center>Tema del mensaje (subject):
<input type="text" name="subjet" size="25"><br><br><br>
<input type="hidden" name="myTextArea" value="<?echo $myTextArea?>">
<table border="1">
<tr>
<td rowspan="3"><select id="sel1" size="10" style="width:150;" multiple>
<option value="0">0</option>
<option value="1">1</option>
<option value="2">3</option>
<option value="3">3</option>
<option value="4">4</option>
<option value="5">5</option>
<option value="6">6</option>
</select></td>
<td><div align="center">
<input name="button" type="button" onClick="insertar()" value="Incluir >">
</div></td>
<td rowspan="3"><select name="select" size="10" multiple id="sel2" style="width:150;">
</select></td>
</tr>
<tr>
<td><div align="center">
<input name="button" type="button" onClick="eliminar()" value="< Sacar">
</div></td>
</tr>
<tr>
<td><div align="center"><input name="button" type="button" onClick="vaciar()" value=" << Vaciar"></div></td>
</tr>
<tr>
<td>
<td> </td>
<td> </td>
</tr>
<tr>
<td> </td>
<td><input name="submit" type="submit" value="Confirmar y enviar"></td>
<td> </td>
</tr>
</table>
</center></form>
</body>
</html> Saludos y gracias nuevamente.