base.php文件，找不到以下代码

在putenv("$item=$v");

是：

require __DIR__ . '/library/think/Loader.php';

// 注册自动加载

Loader::register();

// 注册错误和异常处理机制

Error::register();

// 实现日志接口

if (interface_exists('Psr\Log\LoggerInterface')) {

    interface LoggerInterface extends \Psr\Log\LoggerInterface

    {}

} else {

    interface LoggerInterface

    {}

}

// 注册类库别名

Loader::addClassAlias([

    'App'      => facade\App::class,

    'Build'    => facade\Build::class,

    'Cache'    => facade\Cache::class,

    'Config'   => facade\Config::class,

    'Cookie'   => facade\Cookie::class,

    'Db'       => Db::class,

    'Debug'    => facade\Debug::class,

    'Env'      => facade\Env::class,

    'Facade'   => Facade::class,

    'Hook'     => facade\Hook::class,

    'Lang'     => facade\Lang::class,

    'Log'      => facade\Log::class,

    'Request'  => facade\Request::class,

    'Response' => facade\Response::class,

    'Route'    => facade\Route::class,

    'Session'  => facade\Session::class,

    'Url'      => facade\Url::class,

    'Validate' => facade\Validate::class,

    'View'     => facade\View::class,

]);

if (is_file(ROOT_PATH . '.env')) {
    $env = parse_ini_file(ROOT_PATH . '.env', true);

    foreach ($env as $key => $val) {
        $name = ENV_PREFIX . strtoupper($key);

        if (is_array($val)) {
            foreach ($val as $k => $v) {
                $item = $name . '_' . strtoupper($k);
                putenv("$item=$v");
            }
        } else {
            putenv("$name=$val");
            //写入环境变量，才能在打印$_ENV文件的时候显示出来配置的环境变量
            $_ENV[$name]=$val;
        }
    }
}

找到thinkphp目录下的base.php文件，找到以上代码

在putenv("$item=$v");

后面加一句

$_ENV[$item]=$v;

这样将配置文件中的数组赋值给$_ENV数组即可