我有一个PageController允许添加，编辑和删除页面。对于每个页面，我们可以上传一个单一的图像，我将使用作为横幅。我正在使用蛋糕安全哈希来更改文件名，但我不确定我是否正确地使用它。一些页面可能有相同的图像，所以，使用我下面的代码，删除或更新一个页面将删除所有其他页面的图像有相同的图像...
你能检查一下我下面的代码是否有意义，或者有什么方法可以改进它吗？

public function add()
{
    $page = $this->Pages->newEmptyEntity();

    if ($this->request->is('post'))
    {
        $page = $this->Pages->patchEntity($page, $this->request->getData());

        if(!$page->getErrors()) {
            $image = $this->request->getData('image_file');
            $filename = $image->getClientFilename();
            $filename = \Cake\Utility\Security::hash($image->getClientFilename(), 'sha1');

            $image->moveTo(WWW_ROOT . 'img' . DS . 'pages' . DS . $filename);
            $page->image = $filename;
        }

        if ($this->Pages->save($page))
        {
            $this->Flash->success(__('Your page has been created.'));
            return $this->redirect(['action' => 'index']);
        }

        $this->Flash->error(__('Unable to add your page.'));
    }

    $this->set('page', $page);
}

/**
 * Edit method
 *
 * @param string|null $id Page id.
 * @return \Cake\Http\Response|null|void Redirects on successful edit, renders view otherwise.
 * @throws \Cake\Datasource\Exception\RecordNotFoundException When record not found.
 */
public function edit($id)
{
    $page = $this->Pages->get($id);

    if ($this->request->is(['post', 'put']))
    {
        $this->Pages->patchEntity($page, $this->request->getData());

        if(!$page->getErrors()) {
            $oldImage = $page->image;
            $image = $this->request->getData('image_file');
            $filename = $image->getClientFilename();
            $filename = \Cake\Utility\Security::hash($image->getClientFilename(), 'sha1');

            $image->moveTo(WWW_ROOT . 'img' . DS . 'pages' . DS . $filename);
            $page->image = $filename;

            unlink(WWW_ROOT . 'img' . DS . 'pages' . DS . $oldImage);
        }

        if ($this->Pages->save($page))
        {
            $this->Flash->success(__('Your page has been updated.'));
            return $this->redirect(['action' => 'index']);
        }

        $this->Flash->error(__('Unable to update your page.'));
    }

    $this->set('page', $page);
}

/**
 * Delete method
 *
 * @param string|null $id Page id.
 * @return \Cake\Http\Response|null|void Redirects to index.
 * @throws \Cake\Datasource\Exception\RecordNotFoundException When record not found.
 */
public function delete($id)
{
    $page = $this->Pages->get($id);

    if ($this->Pages->delete($page))
    {
        unlink(WWW_ROOT . 'img' . DS . 'pages' . DS . $page->image);
        $this->Flash->success(__('The {0} page has been deleted.', $page->title));
        return $this->redirect(['action' => 'index']);
    }
}

谢谢你的帮助。