ปัญหา การ คำนวณ totalprice ของสินค้าคำนวณ สินค้าที่มี 1 Recordไม่ได้ แต่คำนวณที่มีมากกว่า 1 Record ได้ ขอทราบวิธีแก้ทีคับ

function calcTotals()
{
    var grandTotal = 0;
    var row = 0;

    while (document.forms['form1'].elements['numpro[]'][row])
    {
        priceObj = document.forms['form1'].elements['numpro[]'][row];
        qtyObj   = document.forms['form1'].elements['numper[]'][row];
        totalObj = document.forms['form1'].elements['total[]'][row];

        if (isNaN(priceObj.value))
        {
            priceObj = '';
        }
        if (isNaN(qtyObj.value))
        {
            qtyObj = '';
        }

        if (priceObj.value && qtyObj.value)
        {
            totalObj.value = (parseFloat(priceObj.value) * parseFloat(qtyObj.value));
            grandTotal = grandTotal + parseFloat(totalObj.value);
        }
        else
        {
            totalObj.value = '';
        }
        row++;
    }
   document.getElementById('grand_total').value = grandTotal;
    
    return;
}

<form name="form1" action="<?php echo htmlentities($_SERVER['PHP_SELF']); ?>" method="POST" >
            <label>รหัสใบเสนอ</label> <input type="text" size="15px" name="quoteid" readonly="readonly" value = "<?php echo $result1 ?>"/ >&nbsp;
            <label>เสนอโดย</label> <input type="text" size="15px" name="empid" value = "<?php echo $result2['EMP_NAME']?> <?php echo $result2['EMP_LNAME'] ?>" readonly="readonly">&nbsp;
            <label>วันที่</label> <input type = "text" size="15px" name="date" value = "<?php echo date("d-m-Y"); ?>" readonly="readonly"></br>

             <label>บริษัทคู่ค้า</label>  <select  name="company" onchange="loadData(this.options[this.selectedIndex].value)">
                      <option value="-2">Select Company</option>
                      <option value="-1">Select All</option>
                      <?php
                        $sql = "SELECT * FROM company order by COM_NAME asc";
                        $obj->query($sql);
                      while($objResult = $obj->fetch_array()){
                        ?>
                        <option value="<?php echo $objResult['COM_ID']?>" ><?php echo $objResult['COM_NAME']?></option>
                        <?php
                      }
                      ?>
            </select>
            <div id="txtHint"></div></br>
            <div>ราคารวมทั้งหมด<input type="text" id="grand_total"readonly="readonly" value="0"></div>
            <input type="submit" name ="submit" value ="เพิ่มรายการเสนอ"/>&nbsp;&nbsp;
            <button type="button" onClick="location.href='main_page.php'" >ยกเลิก</button></br>
        </form>

<?php 
  require('Core.php');
      $obj = new Core; 

      if(!isset($_POST['loadId']) )
      {
        echo "<script language='javascript'> alert('No Data');</script>";
      }
      $loadId = $_POST['loadId'];

          if(isset($_POST['loadId']))
              {
                  if($_POST['loadId'] != -1)
                  {
                        $sql = "SELECT * FROM product,product_color,model,brand,product_type,color WHERE product.COM_ID =  '".$loadId."' and product.PRO_ID = product_color.PRO_ID and 
                        product.MODEL_ID = model.MODEL_ID and product.BRAND_ID = brand.BRAND_ID and product.PRO_TYPE_ID = product_type.PRO_TYPE_ID and product_color.COLOR_ID = color.COLOR_ID"; 
                        $tmp = $obj->query($sql);
                        $check = $obj->num_rows(); 
                  }
                  else
                        $sql = "SELECT * FROM product,product_color,model,brand,product_type,color WHERE  product.PRO_ID = product_color.PRO_ID and 
                        product.MODEL_ID = model.MODEL_ID and product.BRAND_ID = brand.BRAND_ID and product.PRO_TYPE_ID = product_type.PRO_TYPE_ID and product_color.COLOR_ID = color.COLOR_ID"; 
                        $tmp = $obj->query($sql); 
                        $check = $obj->num_rows();
              }
              else
                echo "<script language='javascript'>alert('Error ');window.location='quote.php';</script>";

            if($check > 0)
              {
                   $HTML="";
                   echo "<table width='75%'' border='1' cellspacing='2' cellpadding='0'>
                        <tr>
                        <th>รหัสสินค้า</th>
                        <th>ประเภท</th>
                        <th>ยี่ห้อ</th>
                        <th>รุ่น</th>
                        <th>สี</th>
                        <th>จำนวนที่เสนอ</th>
                        <th>ราคา/หน่วย</th>
                        <th>ราคารวม</th>
                        </tr>";
                      while($row = $obj->fetch_array()){
                        $pro = $row['PRO_ID'];
                         echo "<tr>";
                         echo "<td align='center' >" .$row['PRO_ID'] . "</td>";
                         echo "<td align='center'>" . $row['PRO_TYPE_NAME'] . "</td>";
                         echo "<td align='center'>" . $row['BRAND_NAME'] . "</td>";
                         echo "<td align='center'>" . $row['MODEL_NAME'] . "</td>";
                         echo "<td align='center'>" . $row['COLOR_NAME'] . "</td>";
                         echo "<td align='center'>" .'<input type="number" name="numpro[]" onchange="calcTotals()" >' . "</td>";
                         echo "<td align='center'>" .'<input type="number" name="numper[]" onchange="calcTotals()" >' . "</td>";
                         echo "<td align='center'>" .'<input type="number" name="total[]" id="total" readonly="readonly">' . "</td>";
                         echo "<td>" .'<input type="checkbox" name="select[]" id="select" ' .'onclick="checkAll(this)" value ="'. $pro .'" >'. "</td>";
                   }
                   echo "</table>";
                   echo $HTML;
              }

 ?>