calculate จากภาพนะพี่หนูอยากให้ตรงแถวpriceเวลาใส่จำนวนสินค้าที่ต้องการสั่งซื้อให้ระบบ select ราคาสินค้าแล้ว

<table width="1000" border="0" cellpadding="0" cellspacing="0">
  <tr>
    <td width="50">&nbsp;</td>
    <td width="439"><div align="center">Item</div></td>
    <td width="392"><div align="center">Quantity</div></td>
    <td width="119"><div align="center">Price</div></td>
  </tr>
  <? 
  if(isset($_POST["id_product"])){
	 
						foreach($_POST["id_product"] as $a => $value){
								$item[$k] = $value;
								
								$sql = mssql_query("select * from Product where ID_pro = '$item[$k]'");
								while($result = mssql_fetch_array($sql)){
  ?>
  <tr>
    <td rowspan="3"> <? echo "<img src='../admin/Product/images_product/".$result['Image_pro']."' width='150' height='142'>";?></td>
    <td><div align="left"><span class="style11"><? echo $result['Name_pro'];?></span>
      </div></td>
    <td rowspan="3"><div align="center">
      <input name="Q" type="text" id="Q"  />
    </div></td>
    <td rowspan="3"><div id="targetDiv"></div></td>
  </tr>
 
  <tr>
    <td><div align="left"><span class="style12">Price::</span> <? echo $result['Price_pro'];?>
      </div></td>
    </tr>
  <tr>
    <td><div align="left"><span class="style13">Detail::</span> <? echo $result['Detail_pro_eng'];?>
      </div></td>
    </tr>
  <tr>
    <td colspan="4"><hr /></td>
    </tr>
	 <? } } }?>
     <tr>
       <td height="29" colspan="2">&nbsp;</td>
       <td colspan="2">&nbsp;</td>
     </tr>
     <tr>
    <td height="48" colspan="2"><div align="center"><img src="../images/calculator.gif" width="47" height="48" alt="Click  Calculated" OnClick="if(this.src.search('b2')<0 )Caltotal(); "/></div></td>
    <td colspan="2"><div align="left">Total 
      <input name="total" type="text" id="total" readonly="true" />
      Bath </div></td>
    </tr>
  <tr>
    <td colspan="4">&nbsp;</td>
    </tr>
  <tr>
    <td colspan="4"><hr /></td>
    </tr>
  <tr>
    <td colspan="4"><div align="center"><img src="../images/add_pro.jpg" width="150" height="54" />&nbsp;&nbsp;&nbsp;<img src="../images/confirm.jpg" width="150" height="54" /></div></td>
    </tr>
</table>