Question

我在php中的foreach中出现了这个错误：

为...中的foreach（）提供的参数无效

代码：

$database = new PDO('mysql:host=localhost;dbname=staff_tool', $user, '');
foreach ($database->query('SELECT id,firstname,lastname FROM `staff` SET categorie_bit = 0') as $testx) {
                var_dump($testx);
            }

编辑代码：

foreach ($database->query('SELECT id,firstname,lastname,categorie_bit FROM `staff` WHERE categorie_bit = 1 SET categorie_bit = 0') as $testx) {
            var_dump($testx);
        }

Answer 1

PHP的foreach期望param one是一个可迭代的数组，但似乎你传入一个语句对象（printr）将不再输出select语句）。你可能想尝试一下：

      $stmt = $db->query($sql);
       $stmt->execute();
       $results  = $stmt->fetchAll();

         foreach($results as $result)
                var_dump($result);

Answer 2

$result = $database->query('SELECT id,firstname,lastname,categorie_bit FROM `staff` WHERE categorie_bit = 1 SET categorie_bit = 0');

// always check if you have a valid array ... you do not have any guarantees that SELECT query will return you a result set
if(is_array($result) && count($result) > 0) {
    foreach ($result as $testx) {
        var_dump($testx);
    }
}

Php Foreach错误参数无效

2 个答案: