<?php
if (!$conn)
{
echo "no conecto la DB";
}
$sql="select * from rubros";
?>
<html>
<head>
<title>Documento sin título</title>
</head>
<body>
<form action="select-pros.php" method="post">
<select size="1" name="combo">
<?php
for ($i=0; $i<$num_result; $i++)
{
?>
<option value="<?php echo $reg['id']; ?>"> <?php echo $reg['rubro']; ?> </option>
<?php
}
?>
</select>
<input type="submit" name="cargar" value="enviar">
</form>
</body>
</html>