我想为Wordpress小部件使用一个短代码。我试过插入add_shortcode(\'test_widget\', \'test_load_widget\'); 在底部，但当我试图通过调用[test_widget] 在帖子中，它似乎没有任何作用。我不熟悉短代码和插件。请帮忙。

<?php

// Creating the widget 

class test_widget extends WP_Widget {

    function __construct() {
        parent::__construct(
// Base ID of your widget
                \'test_widget\',
// Widget name will appear in UI
                __(\'Test Widget\', \'test_widget_domain\'),
// Widget description
                array(\'description\' => __(\'Test Widget\', \'test_widget_domain\'),)
        );
    }

// Creating widget front-end
// This is where the action happens
    public function widget($args, $instance) {
        $title = apply_filters(\'widget_title\', $instance[\'title\']);
// before and after widget arguments are defined by themes
        echo $args[\'before_widget\'];
        if (!empty($title))
            echo $args[\'before_title\'] . $title . $args[\'after_title\'];

// This is where you run the code and display the output
        echo __(\'Hello, World!\', \'test_widget_domain\');
        echo $args[\'after_widget\'];
    }

// Widget Backend 
    public function form($instance) {
        if (isset($instance[\'title\'])) {
            $title = $instance[\'title\'];
        } else {
            $title = __(\'New title\', \'wpb_widget_domain\');
        }
// Widget admin form
        ?>
        <p>
            <label for="<?php echo $this->get_field_id(\'title\'); ?>"><?php _e(\'Title:\'); ?></label> 
            <input class="widefat" id="<?php echo $this->get_field_id(\'title\'); ?>" name="<?php echo $this->get_field_name(\'title\'); ?>" type="text" value="<?php echo esc_attr($title); ?>" />
        </p>
        <?php
    }

// Updating widget replacing old instances with new
    public function update($new_instance, $old_instance) {
        $instance = array();
        $instance[\'title\'] = (!empty($new_instance[\'title\']) ) ? strip_tags($new_instance[\'title\']) : \'\';
        return $instance;
    }

}

// Register and load the widget
function test_load_widget() {
    register_widget(\'test_widget\');
}

add_action(\'widgets_init\', \'test_load_widget\');
add_shortcode(\'test_widget\', \'test_load_widget\');