php切换到界面

Question

有没有办法用多态（接口）替换这个开关盒？ 我得到了一个具有不同字段的表单，具体取决于产品类型，它将数据传递到数据库中。

public function typeHandler(){ 
switch($this->type){
  case 'unknown':
    return '';
  case 'dvd':
    $dvd = new Dvd($_POST);
    $product = new Product($_POST);
    $sa = $dvd->getSize();
    $product->setSa($sa);
    $product->save();
    $dvd->save();
    break;
  case 'book':
    $book = new Book($_POST);
    $product = new Product($_POST);
    $sa = $book->getWeight();
    $product->setSa($sa);
    $product->save();
    $book->save();
    break;
  case 'furniture':
    $furniture = new Furniture($_POST);
    $product = new Product($_POST);
    $sa = $furniture->getDimensions();
    $product->setSa($sa);
    $product->save();
    $furniture->save();
    break;
}

}

Answer 1

您可以执行以下操作（一种方法）：

interface Item {
   // This method will replace Dvd::getSize(), Book::getWeight() and Furniture::getDimensions().
   public function getSa();
   public function save();
}

class Dvd implements Item {
   ...
}

class Book implements Item {
   ...
}

class Furniture implements Item {
   ...
}

class ItemFactory {
    private $types = [
        'dvd' => Dvd::class,
        'book' => Book::class,
        'furniture' => Furniture::class,
    ];

    public function create($type, $constructData) {
        if (array_key_exists($type, $this->types)) {
            return new $this->types[$type]($constructData);
        }
        throw new Exception('No such type!');
    }
}

...

public function typeHandler() { 
    $item = (new ItemFactory)->create($this->type, $_POST);
    $product = new Product($_POST);
    $product->setSa($item->getSa());
    $product->save();
    $item->save();
}

注意：不知道为什么单独的Product 类可以与Item 接口完全合并，具体取决于细节。