PHP 編碼規範（十）：類聲明格式、方法分隔與空方法簡寫規範

類聲明格式

<?php
declare(strict_types=1);

namespace App\Entity;

use DateTimeImmutable;
use Doctrine\ORM\Mapping as ORM;

/**
 * 用戶實體
 */
#[ORM\Entity]
class User
{
    // 屬性...
}

大括號風格

• 類/介面/方法/控制結構：左大括號 { 與聲明**同行末尾**，前方一空格
• 右大括號 }：獨佔一行，與對應聲明**左對齊**
• 空體：{} 緊湊書寫，中間無空格換行

<?php
class Sample extends BaseEntity
{
    public function __construct(public string $name) {}

    public function getName(): string
    {
        return $this->name;
    }

    public function setName(string $name): void
    {
        $this->name = $name;
    }

    public function emptyMethod() {}
}

方法之間分隔

• **方法之間空一行** (單個空行)
• 屬性組與第一個方法之間空一行
• 最後一個方法與類右大括號之間**無空行**

<?php
class Service
{
    private Repository $repo;

    public function __construct(Repository $repo)
    {
        $this->repo = $repo;
    }

    public function find(int $id): ?Entity
    {
        return $this->repo->find($id);
    }

    public function save(Entity $entity): void
    {
        $this->repo->save($entity);
    }
}

屬性鉤子 (PHP 8.4) 格式

<?php
class User
{
    public string $email {
        get => $this->email;
        set(string $value) {
            if (!filter_var($value, FILTER_VALIDATE_EMAIL)) {
                throw new InvalidArgumentException('Invalid email');
            }
            $this->email = strtolower($value);
        }
    }
}

Enum 聲明格式 (PHP 8.1+)

<?php
enum Status: string
{
    case Draft = 'draft';
    case Published = 'published';
    case Archived = 'archived';

    public function label(): string
    {
        return match ($this) {
            self::Draft => '草稿',
            self::Published => '已發布',
            self::Archived => '已歸檔',
        };
    }
}

介面聲明格式

<?php
interface PaymentGatewayInterface
{
    public const SUPPORTED_CURRENCIES = ['USD', 'EUR'];

    public function charge(float $amount, string $currency): PaymentResult;
    public function refund(string $transactionId): RefundResult;
}