我试图创建一个小部件，在侧栏中显示帖子，并将帖子ID作为用户的输入。

我的代码的结果是，小部件只显示第一个输入的ID，而忽略其他ID。

示例：如果我在小部件中的输入是1236、1234、1235，小部件前端将只显示id为1236的帖子。

这是我的小部件的代码：

            <?php
            /*
            Plugin Name: Post in Sidebar
            Plugin URI: 
            Description: 
            Author: 
            Version: 1.0
            Author URI: 
            */
            class postInSidebar extends WP_Widget {

                public function __construct() { // Create the Widget

                    parent::__construct(
                        \'postInSidebar\', // ID
                        \'Post in Sidebar\', // Name
                        array( \'description\' => \'Post in Sidebar lets you choose some App Reviews and show them in the sidebar\' )
                        ); // Description

                }

                public function widget( $args, $instance ) { // Frontend

                    extract($args, EXTR_SKIP);

                    echo $before_widget;
                    $title = empty($instance[\'title\']) ? \' \' : apply_filters(\'widget_title\', $instance[\'title\']);

                    if (!empty($title))
                    echo $before_title . $title . $after_title;

                    // start postInSidebar frontend

                    $wp_query = new WP_Query( array (
                        \'post_type\' => \'post\',
                        \'post__in\' => array($instance[\'postsToShow\']),
                        \'orderby\' => \'post__in\'
                    ));

                    ?>

                    <?php if ( $wp_query->have_posts() ) : while ( $wp_query->have_posts() ) : $wp_query->the_post(); ?>

                    <div id="post-<?php the_ID(); ?>" <?php post_class(); ?>>

                        <h2>
                            <a href="<?php the_permalink(); ?>" title="<?php the_title(); ?>">
                                <?php the_title(); ?> - <?php the_ID(); ?>
                            </a>
                        </h2>

                    </div>

                    <?php endwhile; else: ?>
                    <p>No posts yet, go to appearance -> widgets and choose which posts to show here.</p>
                    <?php endif; ?>

                    <?php wp_reset_postdata();

                    // end postInSidebar frontend

                    echo $after_widget;

                }

                public function update( $new_instance, $old_instance ) { // Update

                    $instance = $old_instance;
                        $new_instance = wp_parse_args((array) $new_instance, array(
                            \'title\' => \'\',
                            \'postsToShow\' => \'\'
                        ));
                        $instance[\'title\'] = strip_tags($new_instance[\'title\']);
                        $instance[\'postsToShow\'] = strip_tags($new_instance[\'postsToShow\']);
                    return $instance;

                }

                public function form( $instance ) { // Backend

                    $instance = wp_parse_args( (array) $instance, array(
                        \'title\' => \'\',
                        \'postsToShow\' => \'\'
                    ));
                    $title = esc_attr($instance[\'title\']);
                    $postsToShow = esc_attr($instance[\'postsToShow\']);
                    ?>

                    <!-- title -->

                    <p>
                      <label for="<?php echo $this->get_field_id(\'title\'); ?>">
                        Title:
                        <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); ?>" />
                      </label>
                    </p>

                    <!-- Posts To Show -->

                    <p>
                      <label for="<?php echo $this->get_field_id(\'postsToShow\'); ?>">
                        Posts To Show:
                        <input class="widefat" id="<?php echo $this->get_field_id(\'postsToShow\'); ?>" name="<?php echo $this->get_field_name(\'postsToShow\'); ?>" type="text" value="<?php echo esc_attr($postsToShow); ?>" />
                      </label>
                    </p>

                <?php }

            }

            add_action( \'widgets_init\', function(){
                 register_widget( \'postInSidebar\' );
            });