Kontrak yang harus diimplementasi oleh class. Hanya deklarasi method, tanpa implementasi.
Code reuse mechanism — seperti "copy-paste" method ke dalam class. PHP tidak support multiple inheritance, tapi bisa pakai banyak traits.
<?php
interface Printable {
public function toString(): string;
}
interface Saveable {
public function save(): bool;
}
trait Timestampable {
public string $createdAt;
public function setTimestamp(): void {
$this->createdAt = date("Y-m-d H:i:s");
}
}
trait Sluggable {
public function makeSlug(string $text): string {
return strtolower(str_replace(" ", "-", $text));
}
}
class Article implements Printable, Saveable {
use Timestampable, Sluggable;
public function __construct(public string $title) {
$this->setTimestamp();
}
public function toString(): string {
return "[{$this->createdAt}] {$this->title}";
}
public function save(): bool { return true; }
}
$article = new Article("Belajar PHP OOP");
echo $article->toString() . "
";
echo "Slug: " . $article->makeSlug($article->title) . "
";
echo "Saved: " . ($article->save() ? "Yes" : "No");
?>