php，如何计算while循环的和？

我有一个while循环，它返回一些值：

while ($get_keywords3 = mysql_fetch_array($keywords2)){ 
?>
<tr>
<td><span style="margin: 0 3px;"><?php echo $get_keywords3['grand_total'];?></span></td>
</tr>

<?php } 

我想把它们加在一起：123+234+345+

有什么想法吗

---

谢谢

在while book$var+=$get_关键字3['grand_total']中创建一个单独的变量并求和；或者，如果只想求和，请在查询中求和，然后选择SUMgrand_total-etc

这是做不到的

//To get Project Data
echo "<table>";
echo "<tr>";
echo "<th> Project Code </th>  <th>Project Name</th> <th>Contract Amount </th> <th>Total Paid </th><th>Balance Amount </th>";
echo "</tr>";



while ($voucher_data = mysql_fetch_assoc($voucher_query)) {
        $pid = $voucher_data['pid'];
    $project_data = mysql_fetch_assoc(mysql_query("SELECT * FROM `projectinfo` WHERE `id`='$pid'"));

echo "<tr>";
    echo "<td>".$project_data['project_code']."</td>";
    echo "<td>".$project_data['Project_name']."</td>";
    echo "<td> TK.".$opening_bl = $voucher_data['opening_balance']."</td>";
    echo "<td> TK.".$paid = $voucher_data['SUM(current_pay)']."</td>";
    echo "<td> TK.". $pabe = $opening_bl - $paid."</td>";
echo "</tr>";

?>
</div>
<?php
@$sum_op += $opening_bl;
@$sum_paid += $paid;
@$sum_pabe += $pabe;
}

echo "<tr>";
    echo "<td>Total</td>";
    echo "<td></td>";
    echo "<td> TK.".$sum_op."</td>";
    echo "<td> TK.".$sum_paid."</td>";
    echo "<td> TK.". $pabe = $opening_bl - $sum_pabe."</td>";
echo "</tr>";
echo "</table>";

    echo "<br/>";

$sum = 0;
while ($get_keywords3 = mysql_fetch_array($keywords2)){ 
?>
<tr>
<td><span style="margin: 0 3px;"><?php echo $get_keywords3['grand_total'];?></span></td>
</tr>
<?php 
$sum += $get_keywords3['grand_total']; 
} 

echo $sum; //This will be your total after the adding.

//To get Project Data
echo "<table>";
echo "<tr>";
echo "<th> Project Code </th>  <th>Project Name</th> <th>Contract Amount </th> <th>Total Paid </th><th>Balance Amount </th>";
echo "</tr>";



while ($voucher_data = mysql_fetch_assoc($voucher_query)) {
        $pid = $voucher_data['pid'];
    $project_data = mysql_fetch_assoc(mysql_query("SELECT * FROM `projectinfo` WHERE `id`='$pid'"));

echo "<tr>";
    echo "<td>".$project_data['project_code']."</td>";
    echo "<td>".$project_data['Project_name']."</td>";
    echo "<td> TK.".$opening_bl = $voucher_data['opening_balance']."</td>";
    echo "<td> TK.".$paid = $voucher_data['SUM(current_pay)']."</td>";
    echo "<td> TK.". $pabe = $opening_bl - $paid."</td>";
echo "</tr>";

?>
</div>
<?php
@$sum_op += $opening_bl;
@$sum_paid += $paid;
@$sum_pabe += $pabe;
}

echo "<tr>";
    echo "<td>Total</td>";
    echo "<td></td>";
    echo "<td> TK.".$sum_op."</td>";
    echo "<td> TK.".$sum_paid."</td>";
    echo "<td> TK.". $pabe = $opening_bl - $sum_pabe."</td>";
echo "</tr>";
echo "</table>";

    echo "<br/>";