Fatal error: Uncaught TypeError: Return value of think\App::getThinkPath() must be of the type string, null returned in /www/wwwroot/xianke.baiyun.biz/vendor/topthink/framework/src/think/App.php:460 Stack trace: #0 /www/wwwroot/xianke.baiyun.biz/vendor/topthink/framework/src/think/App.php(227): think\App->getThinkPath() #1 /www/wwwroot/xianke.baiyun.biz/vendor/topthink/framework/src/think/App.php(196): think\App->loadBaseConfig() #2 /www/wwwroot/xianke.baiyun.biz/public/index.php(11): think\App->__construct('/www/wwwroot/xi...') #3 {main} thrown in /www/wwwroot/xianke.baiyun.biz/vendor/topthink/framework/src/think/App.php on line 460