markdown 以编程方式为Drupal 8中的错误页面（404等）设置自定义模板

Posted 2021-05-05

The following code goes in the theme_name.theme file:

```php
/**
 * Implements hook_theme_suggestions_page_alter().
 */
function rootid_theme_theme_suggestions_page_alter(array &$suggestions, array $variables) {

  $path_args = explode('/', trim(\Drupal::service('path.current')->getPath(), '/'));
  $suggestions = theme_get_suggestions($path_args, 'page');
  $http_error_suggestions = [
    'system.401' => 'page__error_page',
    'system.403' => 'page__error_page',
    'system.404' => 'page__error_page',
  ];

  $route_name = \Drupal::routeMatch()->getRouteName();
  if (isset($http_error_suggestions[$route_name])) {
    $suggestions[] = $http_error_suggestions[$route_name];
  }
}
```

Then set up a `page--error-page.html.twig` template :) (Note the underscores in the code are transformed into hyphens in the filename)