[wordpress] 取的文章內容的第一張圖語法

function get_firest_image(){
  ob_start();
  ob_end_clean();
  preg_match('/< *img[^>]*src *= *["\']?([^"\']*)/i', $post->post_content, $matches);
  return $matches[1];
}

和特色圖片一起判斷

function get_firest_image(){
  global $post, $posts;
  $first_img = '';
  if ( has_post_thumbnail() ){
    $first_img = wp_get_attachment_url( get_post_thumbnail_id() );
  }else{
    ob_start();
    ob_end_clean();
    $output = preg_match('/< *img[^>]*src *= *["\']?([^"\']*)/i', $post->post_content, $matches);
    $first_img = $matches[1];
  }

  return $first_img;
}