php - fatal error : Call to undefined function bindParam()

Question

首先，我已经在寻找相同的问题，但找不到解决方案。我的数据库工作正常。除了bindParam() 之外，一切都很好。 var_dump($expr) 也是正确的

$stmt = $pdo->prepare('SELECT * FROM tbl WHERE student_id = :student_id and exam_no = :exam_no');
$student_id = $_POST['student_id'];
$academic_year = $_POST['academic_year'];
$exam_no = $_POST['exam_no'];

$stmt->bindParam(':student_id', $student_id);

$stmt->bindParam(':exam_no', $exam_no);

$stmt->execute();

$blah = $stmt->fetchAll();
$expr = $pdo->prepare('SELECT english FROM tbl WHERE student_id = :student_id and exam_no = :exam_no');
$expr = bindParam(':exam_no', $exam_no);
$expr = bindParam(':student_id', $student_id);
$expr->execute();

获取:“ fatal error :调用未定义的函数bindParam()”，其中$expr = bindParam()所在位置

Answer 1

bindParam 是 PDOStatement 的方法，不是全局函数。 (奇怪的是，你一开始做对了，但后来就错了。)

改变

$expr = bindParam(':exam_no', $exam_no);
$expr = bindParam(':student_id', $student_id);

至

$expr->bindParam(':exam_no', $exam_no);
$expr->bindParam(':student_id', $student_id);