php - 如何修复cakePHP中的Notice (8) : Undefined variable: books [APP/Template\books\index. ctp, line 6]？

Question

我完全是使用 CakePhp 的新手。我已经解决了一些问题，但我又对这个基本问题了如指掌。你能帮我解决这个问题吗？

Notice (8): Undefined variable: books [APP/Template\books\index.ctp, line 6]
Warning (2): Invalid argument supplied for foreach() [APP/Template\books\index.ctp, line 6]

这是我的代码，错误消息指出:

<table>
<thead>
<th>ISBN</th><th>Title</th><th>Author</th>
</thead>
<?php foreach($books as $book): ?>
    <tr>
        <td><?php echo $book['books']['isbn'] ?></td>
        <td><?php echo $book['books']['title'] ?></td>
        <td><?php echo $book['authors']['name'] ?></td>
    </tr>
<?php endforeach; ?>
</table>

这是我的 BooksController.php:

<?php
 /**
 * @property BooksController $BooksController
 */
 namespace App\Controller;
 use App\Controller\AppController;
 class BooksController extends AppController {
  public function display()
  {
    function index() {
        $this->books->recursive = 1;
        $books = $this->books->find('all');
        $this->set('books', $books);
    }
    $this->render('index');
  }
 }
 ?>

这是我的 books.php:

<?php
 /**
 * @property books $books
 */

  class books extends AppModel
  {  
    var $name = 'books';
    var $belongsTo = 'authors';
  }
  ?>

Answer 1

您需要像这样从显示方法中获取索引方法

<?php
   /**
   * @property BooksController $BooksController
   */
    namespace App\Controller;
    use App\Controller\AppController;
    class BooksController extends AppController {
        public function display()
        {
        }
        function index() {
           $this->books->recursive = 1;
           $books = $this->books->find('all');
           $this->set('books', $books);
           $this->render('index');
       }
   }
?>