目前，我正在Java背景下学习PHP和Wordpress开发。如何访问中的变量public function Example_Widget() 从…起public function widget( $args, $instance )? 当我使用var_dump($Example_Widget->$ranNum); 它显示为null。这当然不是真的。这对我来说是全新的。

<?php
        add_action( \'widgets_init\', \'example_load_widgets\' );

        function example_load_widgets() {
            register_widget( \'Example_Widget\' );
        }

        class Example_Widget extends WP_Widget {

        function __construct() {
                parent::__construct(
                    \'Random_Profile_Widget\', // Base ID
                    \'Random Profiles\', // Name
                    array( \'description\' => __( \'Drag this widget to any sidebar to display random profiles.\', \'text_domain\' ), ) // Args
                );
            }

            public function Example_Widget() {

                            $args = array(
                                \'posts_per_page\'   => 99,
                                \'offset\'           => 0,
                                \'category\'         => \'\',
                                \'category_name\'    => \'\',
                                \'orderby\'          => \'post_date\',
                                \'order\'            => \'DESC\',
                                \'include\'          => \'\',
                                \'exclude\'          => \'\',
                                \'meta_key\'         => \'\',
                                \'meta_value\'       => \'\',
                                \'post_type\'        => \'resume\',
                                \'post_mime_type\'   => \'\',
                                \'post_parent\'      => \'\',
                                \'post_status\'      => \'publish\',
                                \'suppress_filters\' => true 
                            );
                            $resumes = get_posts($args);            
                            $ranNum = rand ( 0 , sizeof($resumes) - 1 );
                            $resume = $resumes[$ranNum];                                    
            }
        public function widget( $args, $instance ) { ?>
                    <p><?php var_dump($Example_Widget->$ranNum); ?></p> 
        <?php }
    }

    /* Stop Adding Functions Below this Line */
    ?>