PHP：常量作为函数中的变量 [英] PHP: constant as variable in function

问题描述

我正在尝试使用常量作为函数参数，是否可以检查此常量的类型。

I'm trying to use constant as a function paramter, is it possible to check type of this constant.

我想要的示例：

class ApiError {
  const INVALID_REQUEST = 200;
}

class Response {
  public function status(ApiError $status) {
    //function code here
  }
}

使用情况：

$response = new Response();
$response->status(ApiError::INVALID_REQUEST);

此应检查的是，给定的$ status是类ApiError的常量。

This shoud check that given $status is constant of class ApiError. Is something like this possible?

推荐答案

正如其他提到的那样，没有通用的解决方案。但是，如果您想以一种非常干净的方式进行操作，则可以对要处理的每个对象进行建模（=每个可能的状态），例如：

As the others mentioned, there is no generic solution. But if you'd like to do it in a very clean way, model every "object" that you're dealing with (= every possible status), e.g.:

interface ApiError {   // make it an abstract class if you need to add logic
    public function getCode();
}

class InvalidRequestApiError implements ApiError {
    public function getCode() {
        return 200;
    }
}

// Usage:
$response = new Response();
$response->status( new InvalidRequestApiError() );

class Response {
    public function status(ApiError $status) {
        echo "API status: " . $status->getCode();
    }
    // ...
}

您拥有很多类，因为您封装了简单的数字，而且还具有键入提示的功能。

This leaves you with a lot of classes, because you encapsulate simple numbers, but also with the ability to type-hint.

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