function maketree($rootcatid,$level)
{
$sql="select catid,cat_name
from tbl_name
where parentid=$rootcatid
order by cat_name";

$result=mysql_query($sql);

while (list($DBcatid,$DBcatname)=mysql_fetch_row($result))
{
      $width=($level+1)*24;
 
      if ($width==48)
        $display="    ";
       
      if ($width==72)
        $display="      ";
if ($DBcatid==1)
{
$display.="<option value=$DBcatid>";
}
else
{
$display.="<option value=$DBcatid>";
}
$display.="$DBcatname</option>";
echo $display;
maketree($DBcatid,$level+1);
}
}
?>

<table cellpadding="2" cellspacing="2" border="0" width="width="100%"">
<tr>
<td><select name="">

<? maketree(0,0);?>

</select></td>
</tr>
</table>  

<?php

function maketree( $rootcatid, $level ) {

   if( !is_numeric($rootcatid) || !is_numeric($level) ) {
      return;
   }

   $sql = 'SELECT catid, cat_name FROM tbl_name WHERE parentid = ' . $rootcatid . ' ORDER BY cat_name';

   $result = @mysql_query($sql);

   if( !$result || @mysql_num_rows($result) < 1 ) {
      return;
   }

   $level++;

   while( $sql_data = @mysql_fetch_assoc($result) ){
      $db_catid = $sql_data['catid'];
      $db_catname = $sql_data['cat_name'];
      $display = '';
      for( $i=0;$i<($level*2);$i++ ) {
         $display .= ' ';
      }
      $display .= '<option value="' . $db_catid . '">' . $db_catname . '</option>';
      echo "$display\n";
      maketree($db_catid,$level);
   }
   @mysql_free_result($result);
}

?>