[TOC] ## 示例 ### 概念示例 <details> <summary>main.php</summary> ``` <?php /** * 中介者 */ interface Mediator { public function notify(object $sender, string $event): void; } /** * 具体中介者 */ class ConcreteMediator implements Mediator { private $component1; private $component2; public function __construct(Component1 $c1, Component2 $c2) { $this->component1 = $c1; $this->component1->setMediator($this); $this->component2 = $c2; $this->component2->setMediator($this); } public function notify(object $sender, string $event): void { if ($event == "A") { echo "Mediator reacts on A and triggers following operations:\n"; $this->component2->doC(); } if ($event == "D") { echo "Mediator reacts on D and triggers following operations:\n"; $this->component1->doB(); $this->component2->doC(); } } } class BaseComponent { protected $mediator; public function __construct(Mediator $mediator = null) { $this->mediator = $mediator; } public function setMediator(Mediator $mediator): void { $this->mediator = $mediator; } } class Component1 extends BaseComponent { public function doA(): void { echo "Component 1 does A.\n"; $this->mediator->notify($this, "A"); } public function doB(): void { echo "Component 1 does B.\n"; $this->mediator->notify($this, "B"); } } class Component2 extends BaseComponent { public function doC(): void { echo "Component 2 does C.\n"; $this->mediator->notify($this, "C"); } public function doD(): void { echo "Component 2 does D.\n"; $this->mediator->notify($this, "D"); } } /** * The client code. */ $c1 = new Component1(); $c2 = new Component2(); new ConcreteMediator($c1, $c2); echo "Client triggers operation A.\n"; $c1->doA(); echo "\n"; echo "Client triggers operation D.\n"; $c2->doD(); ``` </details> <br /> 输出 ``` Client triggers operation A. Component 1 does A. Mediator reacts on A and triggers following operations: Component 2 does C. Client triggers operation D. Component 2 does D. Mediator reacts on D and triggers following operations: Component 1 does B. Component 2 does C. ```