您可以使用dynamic_sidebar_params 过滤钩子以查找小部件并向其添加类：

add_filter(\'dynamic_sidebar_params\', \'add_classes_to__widget\'); 
function add_classes_to__widget($params){
    if ($params[0][\'widget_id\'] == "my-widget-1"){ //make sure its your widget id here
        // its your widget so you add  your classes
        $classe_to_add = \'col480 whatever bla bla \'; // make sure you leave a space at the end
        $classe_to_add = \'class=" \'.$classe_to_add;
        $params[0][\'before_widget\'] = str_replace(\'class="\',$classe_to_add,$params[0][\'before_widget\']);
    }
    return $params;
} 

我发现为自定义小部件添加类的另一种方法是使用\'classname\' 构造函数的键，如：

class My_Widget_Class extends WP_Widget {
// Prior PHP5 use the children class name for the constructor…
// function My_Widget_Class()
       function __construct() {
            $widget_ops = array(
                \'classname\' => \'my-class-name\',
                \'description\' => __("Widget for the sake of Mankind",\'themedomain\'),
            );
            $control_ops = array(
                \'id_base\' => \'my-widget-class-widget\'
            );
   //some more code after...

   // Call parent constructor you may substitute the 1st argument by $control_ops[\'id_base\'] and remove the 4th.
            parent::__construct(@func_get_arg(0),@func_get_arg(1),$widget_ops,$control_ops);
        }
}

//This is just an example.
register_sidebar(array(
          \'name\'=> \'Sidebar\',
            \'id\' => \'sidebar-default\',
            \'class\' => \'\',//I never found where this is used...
            \'description\' => \'A sidebar for Mankind\',
            \'before_widget\' => \'<aside id="%1$s" class="widget %2$s">\',//This is the important code!!
            \'after_widget\' => \'</aside>\',
            \'before_title\' => \'<h3>\',
            \'after_title\' => \'</h3>\',
        ));

<aside class="widget my-class-name" id="my-widget-class-widget-N"><!-- where N is a number -->
  <h3>WIDGET TITLE</h3>
  <p>WIDGET CONTENT</p>
</aside>

class My_Widget_Class extends WP_Widget {
    // Better defining the parent argument list …
    function __construct($id_base, $name, $widget_options = array(), $control_options = array())
    {    parent::__construct($id_base, $name, $widget_options, $control_options);
         // Change the class name after
         $this->widget_options[\'classname\'].= \' some-extra\';
    }
}

首先在构造函数中添加自定义占位符类

<?php
public function __construct() {
   $widget_ops  = array(
      \'classname\'                   =>; \'widget_text eaa __eaa__\', //__eaa__ is my placeholder css class
      \'description\'                 =>; __( \'AdSense ads, arbitrary text, HTML or JS.\',\'eaa\' ),
      \'customize_selective_refresh\' =>; true,
   );
   $control_ops = array( \'width\' =>; 400, \'height\' =>; 350 );
   parent::__construct( \'eaa\', __( \'Easy AdSense Ads &amp; Scripts\', \'eaa\' ), $widget_ops, $control_ops );
}
?>

<?php
if ( $instance[\'no_padding\'] ) {
   $args[\'before_widget\'] = str_replace( \'__eaa__\', \'eaa-clean\', $args[\'before_widget\'] );
}
?>

您可以尝试此筛选器：

/**
 * This function loops through all widgets in sidebar 
 * and adds a admin form value to the widget as a class name  
 *  
 * @param array $params Array of widgets in sidebar
 * @return array
*/

add_filter( \'dynamic_sidebar_params\', \'nen_lib_add_class_to_widget\' );
function nen_lib_add_class_to_widget( $params )
{
    foreach( $params as $key => $widget )
    {
        if( !isset($widget[\'widget_id\']) ) continue;

        // my custom function to get widget data from admin form (object)
        $widget_data = nen_get_widget_data($widget[\'widget_id\']) ;

        // check if field excists and has value
        if( isset($widget_data->wm_name) && $widget_data->wm_name )
        {
            // convert and put value in array
            $classes = array( sanitize_title( $widget_data->wm_name ) );

            // add filter, to be able to add more
            $classes = apply_filters( \'nen_lib_add_class_to_widget\' , $classes , $widget[\'widget_id\'] , $widget , $widget_data  );

            // get \'before_widget\' element, set find and replace
            $string     = $params[$key][\'before_widget\'];
            $find       = \'"widget \';
            $replace    = \'"widget \'.implode( \' \' , $classes ).\' \';

            // new value
            $new_before = str_replace( $find , $replace , $string ) ;

            // set new value
            $params[$key][\'before_widget\'] = $new_before;
        }
    }
    return $params;
}