理解MVC:“胖"是什么概念?在模特身上，“瘦"在控制器上?

If you have a fat controller instead, e.g. full with business logic, you are not adhering to the purpose of MVC. A controller's sole responsibility is handling and delegating UI requests to the Model. That's why it should be skinny. It should only contain code necessary for what it's responsible for.

public function fooAction()
{
    if(isset($_POST['bar'])) {
        $bar = Sanitizer::sanitize($_POST['bar']);
        $rows = $this->database->query('SELECT * from table');
        try {
            foreach($rows as $row) {
                $row->foo = $bar;
                $row->save();
            }
        } catch (Exception $e) {
            $this->render('errorPage');
            exit;
        }
        $this->render('successPage');
    } else {
        $this->render('fooPage');
    }
}

什么时候该

public function fooAction()
{
    if(isset($_POST['bar'])) {
        $success = $this->tableGateway->updateFoo($_GET['bar']);
        $page    = $success ? 'successPage' : 'errorPage';
        $this->render($page);
    } else {
        $this->render('fooPage');
    }
}

因为这就是控制器需要知道的全部内容.它不应该更新行.它应该只是告诉模型有人要求进行此更改.更新是管理行的类的责任.此外，控制器不一定要清理该值.