Question

第二次使用POST值:supplier时，脚本不会写入数据库。没有第二个实例，所有内容都会按预期写入。我在做什么错了？

$hostdb = 'localhost';
$namedb = 'dbname';
$userdb = 'username';
$passdb = 'password';
$charset = 'utf8'; 

if (isset($_POST['name'], $_POST['type'] , $_POST['number'] ,$_POST['supplier']  )) {

    // Connect and create the PDO object
    $options = [
        PDO::ATTR_ERRMODE => PDO::ERRMODE_EXCEPTION,
        PDO::ATTR_EMULATE_PREPARES => false,
    ];

    $conn = new PDO("mysql:host=$hostdb;dbname=$namedb;charset=$charset", $userdb, $passdb, $options);

      try{
        $conn->beginTransaction();

    $stmt = $conn->prepare( ' INSERT INTO `Equipment` (name, type, number, supplier, status, managed_by )
VALUES (:name,:type,:number,:supplier,"Ready", :supplier) ' );


    $stmt->execute([
        'name' => $_POST['name'],
        'type' => $_POST['type'],
        'number' => $_POST['number'],
        'supplier' => $_POST['supplier'],
    ]);

Answer 1

3个选项：

给第二次出现一个唯一的标识符:managedBy。请参见下面的示例。
$db->setAttribute(PDO::ATTR_EMULATE_PREPARES, true);
使用?代替命名参数（如注释中指出的那样）

第二个选项（$db->setAttribute...）允许您多次使用同一标识符。取自https://stackoverflow.com/a/40682033/296555。此方法存在安全隐患。我会保持清楚，但将其留在此处作为将来读者的选择。

编辑

使用唯一标识符的示例：

// Notice that we're using a uniquely names placeholder: `:supplier` and `:managedBy`
$stmt = $conn->prepare( ' INSERT INTO `Equipment` (name, type, number, supplier, status, managed_by )
VALUES (:name,:type,:number,:supplier,"Ready", :managedBy) ' );

// Notice that we are referencing those uniquely named placeholders below
// but using the same data `$_POST['supplier']`. 
$stmt->execute([
    'name' => $_POST['name'],
    'type' => $_POST['type'],
    'number' => $_POST['number'],
    'supplier' => $_POST['supplier'],
    'managedBy' => $_POST['supplier'],
]);

在PDO PHP脚本中两次使用相同的POST值| MySQL的

1 个答案: