### 概述 將一個類的接口轉換成可應用的兼容接口。適配器使原本由于接口不兼容而不能一起工作的那些類可以一起工作。 ### 實例 ~~~ interface BookInterface{ public function open(); public function turnPage(); public function getPage(); } class Book implements BookInterface{ private $page; public function open() { $this->page = 1; } public function turnPage() { $this->page++; } public function getPage():int { return $this->page; } } interface EBookInterface { public function unlock(); public function pressNext(); public function getPage(); } class Kindle implements EBookInterface{ private $page = 1; private $totalPages = 100; public function unlock() { } public function pressNext() { $this->page++; } public function getPage():array { return [$this->page,$this->totalPages]; } } class EBookAdapter implements BookInterface{ private $eBook; public function __construct(EBookInterface $eBook) { $this->eBook = $eBook; } public function open() { $this->eBook->unlock(); } public function turnPage() { $this->eBook->pressNext(); } public function getPage():int { return $this->eBook->getPage()[0]; } } $book = new Book(); $book->open(); $book->turnPage(); var_dump($book->getPage()); $kindle = new Kindle(); $book = new EBookAdapter($kindle); $book->open(); $book->turnPage(); $book->turnPage(); $book->turnPage(); var_dump($book->getPage()); ~~~ 結果 ~~~ 2 4 ~~~