除了结果，我的小部件上的一切都在工作！我创建了一个名为“国家名称”的分类法，用于几种自定义帖子类型。我创建这个小部件是为了显示所选国家的导游（CPT）。

该小部件在后端正常工作，但在前端没有得到任何结果（即“未找到列表”）。我在屏幕上回显了$实例，它是正确的，因此我的参数或查询肯定是错误的。有人能说出原因吗？

代码如下：

function widget($args, $instance) {  
extract( $args );   
$title = apply_filters(\'widget_title\', $instance[\'title\']);
$thiscountry = $instance[\'thiscountry\'];
$before_widget = \'<!-- \'.$thiscountry.\' -->\';
echo $before_widget;
if ( $title ) {
    echo $before_title . $title . $after_title;
}
$this->getTourGuides($thiscountry);
echo $after_widget;
}

function getTourGuides($thiscountry) { //html
global $post;
$args = array(
\'posts_per_page\' => -1,
\'post_type\' => array( \'tourguides\' ),
\'tax_query\' => array(
      array(
       \'taxonomy\'      => \'countryname\',
       \'field\' => \'name\', // also tried \'slug\'
        \'terms\' => $thiscountry,
    ),    
  ),
);

//echo $thiscountry;
$listings = new WP_Query( $args);
if($listings->found_posts > 0) {
    echo \'<ul class="guides_widget">\';
        while ($listings->have_posts()) {
            /* Get custom post type fields */
            $ecpt_website = get_post_meta( get_the_ID(), \'ecpt_website\', true );

            $listings->the_post();              
            $listItem = \'<li>\';
            $listItem .= \'<a href="\' . $ecpt_website . \'">\';
            $listItem .= get_the_title() . \'</a>\';
            $listItem .= \'</li>\';
            echo $listItem;
        } // end while
    echo \'</ul>\';
    wp_reset_postdata();
  }else{
    echo \'<p style="padding:25px;">No listing found</p>\';
  }
}

// constructor
function __construct() {
parent::__construct(
    \'btn_tour_guides_by_country\', // Base ID
    \'BTN Tour Guides by Country\', // Name
    array(\'description\' => __( \'Display List of Tour Guides by Country in a Sidebar\'))
   );
}
function update($new_instance, $old_instance) {
$instance = $old_instance;
$instance[\'title\'] = strip_tags($new_instance[\'title\']);
$instance[\'thiscountry\'] = strip_tags($new_instance[\'thiscountry\']);
return $instance;
}

// widget form creation
function form($instance) {
if( $instance) {
    $title = esc_attr($instance[\'title\']);
    $thiscountry = esc_attr($instance[\'thiscountry\']);
} else {
    $title = \'Tour Operators\';
    $thiscountry = \'\';
}
?>
    <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 $title; ?>" />
    </p>
    <p>
    <label for="<?php echo $this->get_field_id(\'thiscountry\'); ?>"><?php _e(\'Country:\'); ?></label>
    <select id="<?php echo $this->get_field_id(\'thiscountry\'); ?>"  name="<?php echo $this->get_field_name(\'thiscountry\'); ?>">
        <?php 
        $taxonomy = \'countryname\';
        $queried_term = get_term_by( \'slug\', get_query_var($taxonomy) );
        $terms = get_terms($taxonomy);
        //echo $term->slug;
        if ( $terms !== 0 ) {
            foreach ( $terms as $term ) {?> 
         <?php                     
            echo \'<option \'.selected($instance[\'thiscountry\'], $term->name).\' value="\' . $term->name . \'" id="\' . $term->name . \'">\', $term->name, \'</option>\';     

               ?>

                  <?php                
            }
        }
         ?>

        <?php ?>
    </select>
    </p>

<?php
}