เลือก checkbox หลาย ๆ อัน แล้วมันลงเพียง อันเดียวครับ ช่วยแนะนำด้วยครับ ท่าน

$sql = "select * from  catalog where category='$category' and price!='0' order by idp asc";  
echo "<table width=\"100%\" cellspacing=2 cellpadding=5><tr bgcolor=#F0F8FF>";
$array = "";
$result = mysql_db_query($dbname,$sql);
$i=1;
while($array=mysql_fetch_array($result)){
$i=$i+1;
$bgcolor = ($bgcolor=="white") ? "F0F8FF" : "white";
echo "<td  align=right style=\"font-size:10pt\">$array[2]</td>";
$type=0;
if($array[9]==1) $type=1;
if($array[10]==1) $type=2;
if($array[6]==1) $type=3;

echo "<form method=\"POST\" action=\"index.php?action=order\" name=\"productlist\"  >


<td><input type=checkbox name=checkbox value=\"".base64_encode($array[2])."\"></Td>
<input type=hidden name=pid value=\"$array[0]\">
<input type=hidden name=type value=\"$type\">
<input type=hidden name=pname value=\"".base64_encode($array[2])."\">
<input type=hidden name=price value=\"$array[8]\">";



echo"<td align=center>";
echo "<select name=\"test1\">
<option value=\"$array[2]\" >เพิ่มเติม</option>";
for($d=0; $d<count($extend); $d++)
	{
			echo "<option>$extend[$d]</option>";
	}
			echo"</td></select>


<td align=center ><input type=text name=\"qtys\" size=1 value=\"1\" style=\"font: 8pt;width:45\" autocomplete=\"off\"></td>

";
if(($i%3)==1){
echo "</tr><tr bgcolor=$bgcolor>";
}}
echo"    
             <td align=center><input type=submit  name=submit  value=\"OK\" style=\"font:10pt;width:45;height:30;  background color=inactivecaptiontext\"></td>";