Answer 1

$route['engineering-resources/login'] = "resources/login";

这不会路由到engineering-resources/login/validate_credentials到resources/login/validate_credentials

你应该有这样的东西：

// not tested
$route['engineering-resources/login/(\S*)'] = "resources/login/$1";

还有一件事是，如果你正在使用路线，你也应该使用你的观点中的路线..

echo form_open('engineering-resources/login/validate_credentials');