Hola espero me puedan ayudar, he estado intentando ocultar los combos cuando estan sobre el encabezado, una opcion que usaba era que cuando estuvieran debajo de del encabezado ocultaba toda la fila, necesito que solo se oculten los combos, ojala me puedan ayudar aqui esta el codigo
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<title>Untitled</title>
<style>
td {font-size:30pt}
th {font-size:20pt; background:navy; color:white;}
</style>
<script language="JavaScript">
attachEvent("onscroll", mover);
function mover()
{
document.all('header').style.position='absolute';
document.all('header').style.top=document.body.scr ollTop
}
</script>
</head>
<body>
<table border="2" id="tabla" name="tabla">
<tr id="header">
<th>#</td>
<th>Nombre</td>
<th>Apellido Paterno</td>
<th>Apellido Materno</td>
<th>Direccion</td>
<th>Colonia</td>
<th>Quiere trabajar en</td>
</tr>
<tr>
<td nowrap>1</td>
<td nowrap>Juan Manuel</td>
<td nowrap>Perez</td>
<td nowrap>Perez</td>
<td nowrap>Constitucion #567</td>
<td nowrap>Centro</td>
<td nowrap>
<select>
<option>Aguascalientes</option>
<option>Guadalajara</option>
<option>SAn Luis Potosi</option>
<option>Durango</option>
<option>Monterrey</option>
</select>
</td>
</tr>
<tr>
<td nowrap>1</td>
<td nowrap>Juan Manuel</td>
<td nowrap>Perez</td>
<td nowrap>Perez</td>
<td nowrap>Constitucion #567</td>
<td nowrap>Centro</td>
<td nowrap>
<select>
<option>Aguascalientes</option>
<option>Guadalajara</option>
<option>SAn Luis Potosi</option>
<option>Durango</option>
<option>Monterrey</option>
</select>
</td>
</tr>
<tr>
<td nowrap>1</td>
<td nowrap>Juan Manuel</td>
<td nowrap>Perez</td>
<td nowrap>Perez</td>
<td nowrap>Constitucion #567</td>
<td nowrap>Centro</td>
<td nowrap>
<select>
<option>Aguascalientes</option>
<option>Guadalajara</option>
<option>SAn Luis Potosi</option>
<option>Durango</option>
<option>Monterrey</option>
</select>
</td>
</tr>
<tr>
<td nowrap>1</td>
<td nowrap>Juan Manuel</td>
<td nowrap>Perez</td>
<td nowrap>Perez</td>
<td nowrap>Constitucion #567</td>
<td nowrap>Centro</td>
<td nowrap>
<select>
<option>Aguascalientes</option>
<option>Guadalajara</option>
<option>SAn Luis Potosi</option>
<option>Durango</option>
<option>Monterrey</option>
</select>
</td>
</tr>
<tr>
<td nowrap>1</td>
<td nowrap>Juan Manuel</td>
<td nowrap>Perez</td>
<td nowrap>Perez</td>
<td nowrap>Constitucion #567</td>
<td nowrap>Centro</td>
<td nowrap>
<select>
<option>Aguascalientes</option>
<option>Guadalajara</option>
<option>SAn Luis Potosi</option>
<option>Durango</option>
<option>Monterrey</option>
</select>
</td>
</tr>
<tr>
<td nowrap>1</td>
<td nowrap>Juan Manuel</td>
<td nowrap>Perez</td>
<td nowrap>Perez</td>
<td nowrap>Constitucion #567</td>
<td nowrap>Centro</td>
<td nowrap>
<select>
<option>Aguascalientes</option>
<option>Guadalajara</option>
<option>SAn Luis Potosi</option>
<option>Durango</option>
<option>Monterrey</option>
</select>
</td>
</tr>
<tr>
<td nowrap>1</td>
<td nowrap>Juan Manuel</td>
<td nowrap>Perez</td>
<td nowrap>Perez</td>
<td nowrap>Constitucion #567</td>
<td nowrap>Centro</td>
<td nowrap>
<select>
<option>Aguascalientes</option>
<option>Guadalajara</option>
<option>SAn Luis Potosi</option>
<option>Durango</option>
<option>Monterrey</option>
</select>
</td>
</tr>
<tr>
<td nowrap>1</td>
<td nowrap>Juan Manuel</td>
<td nowrap>Perez</td>
<td nowrap>Perez</td>
<td nowrap>Constitucion #567</td>
<td nowrap>Centro</td>
<td nowrap>
<select>
<option>Aguascalientes</option>
<option>Guadalajara</option>
<option>SAn Luis Potosi</option>
<option>Durango</option>
<option>Monterrey</option>
</select>
</td>
</tr>
<tr>
<td nowrap>1</td>
<td nowrap>Juan Manuel</td>
<td nowrap>Perez</td>
<td nowrap>Perez</td>
<td nowrap>Constitucion #567</td>
<td nowrap>Centro</td>
<td nowrap>
<select>
<option>Aguascalientes</option>
<option>Guadalajara</option>
<option>SAn Luis Potosi</option>
<option>Durango</option>
<option>Monterrey</option>
</select>
</td>
</tr>
<tr>
<td nowrap>1</td>
<td nowrap>Juan Manuel</td>
<td nowrap>Perez</td>
<td nowrap>Perez</td>
<td nowrap>Constitucion #567</td>
<td nowrap>Centro</td>
<td nowrap>
<select>
<option>Aguascalientes</option>
<option>Guadalajara</option>
<option>SAn Luis Potosi</option>
<option>Durango</option>
<option>Monterrey</option>
</select>
</td>
</tr>
<tr>
<td nowrap>1</td>
<td nowrap>Juan Manuel</td>
<td nowrap>Perez</td>
<td nowrap>Perez</td>
<td nowrap>Constitucion #567</td>
<td nowrap>Centro</td>
<td nowrap>
<select>
<option>Aguascalientes</option>
<option>Guadalajara</option>
<option>SAn Luis Potosi</option>
<option>Durango</option>
<option>Monterrey</option>
</select>
</td>
</tr>
<tr>
<td nowrap>1</td>
<td nowrap>Juan Manuel</td>
<td nowrap>Perez</td>
<td nowrap>Perez</td>
<td nowrap>Constitucion #567</td>
<td nowrap>Centro</td>
<td nowrap>
<select>
<option>Aguascalientes</option>
<option>Guadalajara</option>
<option>SAn Luis Potosi</option>
<option>Durango</option>
<option>Monterrey</option>
</select>
</td>
</tr>
<tr>
<td nowrap>1</td>
<td nowrap>Juan Manuel</td>
<td nowrap>Perez</td>
<td nowrap>Perez</td>
<td nowrap>Constitucion #567</td>
<td nowrap>Centro</td>
<td nowrap>
<select>
<option>Aguascalientes</option>
<option>Guadalajara</option>
<option>SAn Luis Potosi</option>
<option>Durango</option>
<option>Monterrey</option>
</select>
</td>
</tr>
<tr>
<td nowrap>1</td>
<td nowrap>Juan Manuel</td>
<td nowrap>Perez</td>
<td nowrap>Perez</td>
<td nowrap>Constitucion #567</td>
<td nowrap>Centro</td>
<td nowrap>
<select>
<option>Aguascalientes</option>
<option>Guadalajara</option>
<option>SAn Luis Potosi</option>
<option>Durango</option>
<option>Monterrey</option>
</select>
</td>
</tr>
</table>
</body>
</html>
este es un ejemplito de como me molesta el combo cuando hago scrolltop
