Thêm nút hữu ích vào bài viết trong Wordpess

// them huu ich va tam duoc vao bai viet cua caodem
function ip_post_likes($content) {
if(is_singular('post')) {
ob_start();
?>

Chào nickname; ?>! Bạn thấy nội dung này thế nào? 


Hữu ích 
Tạm được 


$output = ob_get_clean();
return $content . $output;
}else {
return $content;
}
}
add_filter('the_content', 'ip_post_likes');
function ip_get_like_count($type = 'likes') {
$current_count = get_post_meta(get_the_id(), $type, true);
return ($current_count ? $current_count : 0);
}
function ip_process_like() {
$processed_like = false;
$redirect = false;
if(is_singular('post')) {
if(isset($_GET['post_action'])) {
if($_GET['post_action'] == 'like') {
$like_count = get_post_meta(get_the_id(), 'likes', true);
if($like_count) {
$like_count = $like_count + 1;
}else {
$like_count = 1;
}
$processed_like = update_post_meta(get_the_id(), 'likes', $like_count);
}elseif($_GET['post_action'] == 'dislike') {
$dislike_count = get_post_meta(get_the_id(), 'dislikes', true);
if($dislike_count) {
$dislike_count = $dislike_count + 1;
}else {
$dislike_count = 1;
}
$processed_like = update_post_meta(get_the_id(), 'dislikes', $dislike_count);
}
if($processed_like) {
$redirect = get_the_permalink();
}
}
}
if($redirect) {
wp_redirect($redirect);
die;
}
}
add_action('template_redirect', 'ip_process_like');

.ok-like a {
margin-right: 10px;
text-decoration: none;
color: #111;
font-size: 13px;
font-weight: bold;
background:#fff444;
padding:5px 8px 5px 8px;
border-radius:7px;
display: inline-block;
}
.ok-like a:hover{color:#fff;background:#0c0}
.title-like{color:#ccc;font-size:15px;}
.yes-likes {
padding: 20px;
background: #4b238a;
text-align: center;
border-radius: 10px;
}
@media (max-width: 400px){
.ok-like a{font-size:10px}
}