我在这里做错了什么

更改：

if($_GET['step'] == 2)

至：

if((int)$_GET['step'] === 2)

和：

public function UpdateReason($reason, $bundlereference) {
    $sql = "UPDATE `ArchiveBundle`
        SET `Issue` = " . $reason . "
        WHERE `BundleReference` = " . $bundlereference .    
        ";";
    mysql_select_db(DB_DATABASE_NAME, $this->conn);
    return mysql_query($sql, $this->conn);
}

至：

public function UpdateReason($reason, $bundlereference) {
    mysql_select_db(DB_DATABASE_NAME, $this->conn);
    $_reason = mysql_real_escape_string($reason,$this->conn);
    $_bundlereference = mysql_real_escape_string($bundlereference,$this->conn);
    $sql = "UPDATE `ArchiveBundle`
            SET `Issue` = '" . $_reason . "'
            WHERE `BundleReference` = '" . $_bundlereference . "'";
    return mysql_query($sql, $this->conn);
}

试试看。代码尚未经过测试，但这是一个很好的起点。

要尝试调试这里发生的事情，请执行以下操作：

public function UpdateReason($reason, $bundlereference) {
    error_reporting(E_ALL ^ E_NOTICE);
    $db_selected = mysql_select_db(DB_DATABASE_NAME, $this->conn);
    if (!$db_selected) {
        die("Can't use db : " . mysql_error());
    }
    $_reason = mysql_real_escape_string($reason,$this->conn);
    $_bundlereference = mysql_real_escape_string($bundlereference,$this->conn);
    $sql = "UPDATE `ArchiveBundle`
            SET `Issue` = '" . $_reason . "'
            WHERE `BundleReference` = '" . $_bundlereference . "'";
    mysql_query($sql, $this->conn);
    die(mysql_error());
}

此外，在提交表单时，您似乎没有传递Reference参数，因此在发布表单时if（isset（$_GET['Reference']）将失败。我更改了下面的表和表单代码，使其更具可读性，在表单提交时传递Reference参数，并在获取数据集之前更新数据库记录，以便您可以看到返回的表中更新的记录。

// First of all initialise the user and check for permissions
require_once "/var/www/users/user.php";
$user = new CHUser(2);

// Initialise the template
require_once "/var/www/template/template.php";
$template = new CHTemplate();
// And create a cid object
require_once "/var/www/Testing/DisplayWIPOnLocation.php";
$BundleProgress= new CHWIPProgress();

if(isset($_GET['Reference'])){
    if($_GET['step'] == 2) {
        $BundleProgress->UpdateReason($_POST['reason'],$_POST['bundlereference']);
    }
    $todays_date = date("Y-m-d H:i:s");
    $content .= " <h3> Details for Bundle : $reference </h3> ";
    $bundle = $BundleProgress->GetBundle($_GET['Reference']);   
    $reference = $_GET['Reference'];
    // Now show the details
    foreach($bundle as $x){
        $content .= "
                    <table>
                        <tr><th> Location </th><td>" . $x['Description'] . "</td></tr>
                        <tr><th> Works Order Number </th><td>" . $x['WorksOrder'] . "</td></tr>
                        <tr><th> Bundle Number </th><td>" . $x['Number'] . "</td></tr>
                        <tr><th>Qty Issued</th><td>" . $x['Qty'] . "</td></tr>
                        <tr><th>Bundle Reference </th><td>" . $x['Reference'] . "</td></tr>
                        <tr><th>Style description</th><td>" . $x['Stock'] . "</td></tr>
                        <tr><th>Due Date</th><td>" . $x['DueDate'] . "</td></tr>
                        <tr><th>Date In </th><td>" . $x['DateIN'] . "</td></tr>
                        <tr><th>Date Out</th><td>" . $x['DateOUT'] . "</td></tr>
                        <tr><th>Last Code</th><td>" . $x['Last'] . "</td></tr>
                    </table>
                    <br>";
    }
    $content .= "<table>
                    <form action='viewBundle.php?Reference=" . $_GET['Reference'] . "&step=2' method='post'>
                        <p>Reason: <input type='text' name='reason' /></p><br/>
                        <p><input type='hidden' name='bundlereference' id='Username' value='" . $x['Reference'] . "' /></p>
                        <input type='submit' name ='add'/>
                    </form>
                </table>";   
} else {
    $content .= "<h3>Something has gone wrong</h3>
                <br>
                <a href='index.php?location=" . $x['Description'] . "'> Return to Previous Page </a> 
                ";
}
$template->SetTag("content", $content);
echo $template->Display();

我可以建议您先检查mysql_query返回的内容来分解它吗。可能是这个特定变量的定义不正确。还要记住在查询中的值中添加引号。