我有下面的代码，我正试图获得一个数组中的一行数据。我不确定我是否把准备好的声明和pdo混在一起了。
我得到以下错误：

Uncaught Error: Cannot use object of type mysqli_stmt as array in...

代码：

// Prepare a select statement
 $sql = "SELECT * FROM pupils WHERE pupil_id = ?";

 if($stmt = $mysqli->prepare($sql)){
     // Bind variables to the prepared statement as parameters
     $stmt->bind_param("i", $param_pupil_id);
     // Set parameters

     $param_pupil_id = $_POST['pupil_num'];
   // Attempt to execute the prepared statement

     if($stmt->execute()){

      $stmt->store_result(); 

         if($stmt->num_rows == 1){   

           $stmt->bind_result($id, $pupil_id, $name, $eal, $pp);
//Updated code
           echo $stmt->fetch()->$name;

         } else{
             echo "error";
         }
     } else{
         echo "Oops! Something went wrong. Please try again later.";
     }
 }