在PHP中传递全局配置[关闭]

Question

I have the following:

_CONFIG.php

<?php namespace App\go;
define('x_client_id', 'client');
define('x_client_secret', '');
define('x_username', 'ervice');

another.php

<?php namespace App\go;

include _CONFIG.php;
class goapp
{
    protected $_client_id = x_client_id;
    protected $_client_secret = x_client_secret;
    protected $_username = x_username;

This does not seem to pass or load the variables. Is there a correct way to move the variables out of the files and create a master config?

Answer 1

You cannot initialize class properties to constants defined using the define construct. Reference this quote from the manual:

They are defined by using one of the keywords public, protected, or private, followed by a normal variable declaration. This declaration may include an initialization, but this initialization must be a constant value--that is, it must be able to be evaluated at compile time and must not depend on run-time information in order to be evaluated.

The only thing you can initialize class properties to is what is available to the interpreter during compile time and not runtime. What this basically boils down to is that you cannot initialize these properties to anything that requires other code to run first in order to be defined.

An exception is the const keyword, since these are evaluated at compile time.