如何使用PHP和MySQL从数据库中删除选中的复选框？

Question

我一直试图解决这个问题，但都无济于事。我试图从表中删除多个复选框。删除功能确实有效，但它只删除最年轻id的数据。

delete_Pm功能：

function deletePm(pmid,wrapperid,originator){
    var conf = confirm(originator+"Press OK to confirm deletion of this message and its replies");
    if(conf != true){
        return false;
    }
    var ajax = ajaxObj("POST", "php_parsers/pm_system.php");
    ajax.onreadystatechange = function() {
        if(ajaxReturn(ajax) == true) {
            if(ajax.responseText == "delete_ok"){
                _(wrapperid).style.display = 'none';
            } else {
                alert(ajax.responseText);
            }
        }
    }
    ajax.send("action=delete_pm&pmid="+pmid+"&originator="+originator);
}

表的PHP代码：

$table .= '
              <tr id="'.$pmid.'">
                    <td><center><input type="checkbox" id="cb1_'.$pmid.'" name="cb1_'.$pmid.'[]" class="cbgroup1"></center></td>
                    <td><a href="pm_message.php?u='.$log_username.'&pmid='.$pmid.'" onclick="markRead(\''.$pmid.'\',\''.$sender.'\')">'.$sender.'</a></td>
                    <td>'.$receiver.'</td>
                    <td>'.$subject.'</td>
                    <td>'.$time.'</td>
              </tr>';   

表格的HTML：

<table class="table table-bordered" style="margin-top: 20px;">
            <thead>
              <tr>
                <th><center><input type="checkbox" value="" id="cbgroup1_master" onchange="togglecheckboxes(this,'cbgroup1')"></center></th>
                <th>Sender</th>
                <th>Receiver</th>
                <th>Subject</th>
                <th>Date</th>
              </tr>
            </thead>
            <tbody>
                <?php echo $table; ?>
            </tbody>

来自pm_system.php的删除函数的PHP：

<?php
// Delete PM
if (isset($_POST['action']) && $_POST['action'] == "delete_pm"){
    if(!isset($_POST['pmid']) || $_POST['pmid'] == ""){
        mysqli_close($db);
        echo "id_missing";
        exit();
    }
    $pmid = preg_replace('#[^0-9]#', '', $_POST['pmid']);
    if(!isset($_POST['originator']) || $_POST['originator'] == ""){
        mysqli_close($db);
        echo "originator_missing";
        exit();
    }
    $originator = preg_replace('#[^a-z0-9]#i', '', $_POST['originator']);
    // see who is deleting
    if ($originator == $log_username) {
        $updatedelete = mysqli_query($db, "UPDATE pm SET sdelete='1' WHERE id='$pmid' LIMIT 1");
        }
    if ($originator != $log_username) {
        $updatedelete = mysqli_query($db, "UPDATE pm SET rdelete='1' WHERE id='$pmid' LIMIT 1");
        }
    mysqli_close($db);
    echo "delete_ok";
    exit();
}
?>