如何获得热门视频youtube API PHP？

I try using the chart parameter to get trending videos, but it says that chart is not a valid parameter. I am using PHP. I have the region and category and everything set fine. Is this a bug? How do I do it?

here is the code I have

  $searchResponse = $youtube->search->listSearch('id,snippet', array(
        //'type' => 'video',
        'part' => 'snippet',
          'location' => 'GB',
          'videoCategoryId' => '23',
         'chart' => 'mostPopular',
        'order' => 'date',
        'maxResults' => '50'
    ));

says: An client error occurred: (list) unknown parameter: 'chart'

You are looking for Videos list endpoint not Search list endpoint, you can get the most popular videos for your regionCode & videoCategoryId with :

$videosResponse = $youtube->videos->listVideos('snippet', array(
    'chart' => 'mostPopular',
    'maxResults' => 50,
    'regionCode' => 'GB',
    'videoCategoryId' => '23'
));