从子域访问时需要切换主题。子域中未安装任何内容。我已将一个子域设置为指向原始域的CNAME。然后，通过查看$\\u服务器[\'SERVER\\u NAME\']，检测访问者是否在子域上。查看了各种来源并发现了此代码，但无法使其正常工作。

注：我是个新手

// regular site url
$my_url = \'http://example.com\';

// subdomain you want a different theme on
$my_sub_url = \'http://sub.example.com\';

// subdomain prefix, used to test whether primary or subdomain
$my_prefix = \'sub.\';

// folder name of theme to use instead on subdomain
$my_theme_name = \'my_mobile_theme\';


add_filter( \'template\'          , \'my_change_theme\' );
add_filter( \'option_template\'   , \'my_change_theme\' );
add_filter( \'option_stylesheet\' , \'my_change_theme\' );

// these 2 actions rewrite all urls in the body
// from main to sub domain
add_action( \'wp_head\'           , \'my_buffer_start\' );
add_action( \'wp_footer\'         , \'my_buffer_end\' );

// TRUE, if this is the subdomain, false otherwise
public function my_is_subdomain() {
  global $my_prefix;
  if( strpos( $_SERVER[\'SERVER_NAME\'], $my_prefix ) !== FALSE ) {
    return TRUE;
  }
  return FALSE;
}

// if this is the subdomain, return new theme
// otherwise, return original theme
public function my_change_theme( $theme ) {
  global $my_theme_name;
  if( my_is_subdomain() ) {
    return $my_theme_name;
  }
  return $theme;
}

public function my_buffer_start() {
  ob_start(\'my_buffer_cb\');
}

public function my_buffer_end() {
  ob_end_flush();
}

// replace primary url with subdomain url in body
// so that all links keep user on the subdomain
public function my_buffer_cb( $buffer ) {
  global $my__url, $my_sub_url;
  if( ! my_is_subdomain() ) {
    return $buffer;
  }

  // replace main domain with sub domain
  $buffer = str_replace( $my_url, $my_sub_url, $buffer);

  // !!! NOTE - you may not want to replace EVERY instance
  // for example, you may want to keep social media urls
  // intact, or rel="canonical", or links specifically
  // designed to switch between the primary and subdomain

  return $buffer;
}