PHP 8新特性实战：属性注解与匹配模式的现代应用指南

三、电商数据验证系统实战

3.1 验证注解定义

#[Attribute(Attribute::TARGET_PROPERTY)]
class ValidateLength {
    public function __construct(
        public int $min,
        public ?int $max = null,
        public string $message = '长度验证失败'
    ) {}
}

#[Attribute(Attribute::TARGET_PROPERTY)]
class ValidateEmail {
    public function __construct(
        public string $message = '邮箱格式不正确'
    ) {}
}

#[Attribute(Attribute::TARGET_PROPERTY)]
class ValidateRange {
    public function __construct(
        public int|float $min,
        public int|float $max,
        public string $message = '数值超出范围'
    ) {}
}

#[Attribute(Attribute::TARGET_PROPERTY)]
class ValidateRegex {
    public function __construct(
        public string $pattern,
        public string $message = '格式验证失败'
    ) {}
}

3.2 数据模型定义

class UserRegistration {
    #[ValidateLength(min: 2, max: 50, message: '用户名长度应在2-50字符之间')]
    #[ValidateRegex(pattern: '/^[a-zA-Z0-9_]+$/', message: '用户名只能包含字母、数字和下划线')]
    public string $username;
    
    #[ValidateEmail(message: '请输入有效的邮箱地址')]
    public string $email;
    
    #[ValidateLength(min: 8, message: '密码长度至少8位')]
    public string $password;
    
    #[ValidateRange(min: 18, max: 100, message: '年龄应在18-100岁之间')]
    public int $age;
    
    #[ValidateRegex(pattern: '/^1[3-9]d{9}$/', message: '请输入有效的手机号码')]
    public string $phone;
    
    public function __construct(array $data) {
        foreach ($data as $key => $value) {
            if (property_exists($this, $key)) {
                $this->$key = $value;
            }
        }
    }
}

3.3 验证器核心实现

class AdvancedValidator {
    private array $errors = [];
    
    public function validate(object $object): bool {
        $reflection = new ReflectionClass($object);
        
        foreach ($reflection->getProperties() as $property) {
            $value = $property->getValue($object);
            $propertyName = $property->getName();
            
            foreach ($property->getAttributes() as $attribute) {
                $validator = $attribute->newInstance();
                if (!$this->validateAttribute($validator, $value, $propertyName)) {
                    $this->errors[$propertyName][] = $validator->message;
                }
            }
        }
        
        return empty($this->errors);
    }
    
    private function validateAttribute($validator, $value, string $propertyName): bool {
        return match(get_class($validator)) {
            ValidateLength::class => $this->validateLength($validator, $value),
            ValidateEmail::class => $this->validateEmail($validator, $value),
            ValidateRange::class => $this->validateRange($validator, $value),
            ValidateRegex::class => $this->validateRegex($validator, $value),
            default => true
        };
    }
    
    private function validateLength(ValidateLength $validator, $value): bool {
        $length = strlen((string)$value);
        if ($length min) return false;
        if ($validator->max !== null && $length > $validator->max) return false;
        return true;
    }
    
    private function validateEmail(ValidateEmail $validator, $value): bool {
        return filter_var($value, FILTER_VALIDATE_EMAIL) !== false;
    }
    
    private function validateRange(ValidateRange $validator, $value): bool {
        return $value >= $validator->min && $value max;
    }
    
    private function validateRegex(ValidateRegex $validator, $value): bool {
        return preg_match($validator->pattern, (string)$value) === 1;
    }
    
    public function getErrors(): array {
        return $this->errors;
    }
}

3.4 完整使用示例

// 使用示例
$userData = [
    'username' => 'john_doe123',
    'email' => 'john@example.com',
    'password' => 'securepassword',
    'age' => 25,
    'phone' => '13800138000'
];

$user = new UserRegistration($userData);
$validator = new AdvancedValidator();

if ($validator->validate($user)) {
    echo "数据验证通过！";
    // 执行注册逻辑
} else {
    echo "数据验证失败：";
    print_r($validator->getErrors());
}