非插件实现wordpress文章点赞功能

add_action('wp_ajax_nopriv_bigfa_like', 'bigfa_like');
add_action('wp_ajax_bigfa_like', 'bigfa_like');
function bigfa_like(){
    global $wpdb,$post;
    $id = $_POST["um_id"];
    $action = $_POST["um_action"];
    if ( $action == 'ding'){
		$bigfa_raters = get_post_meta($id,'bigfa_ding',true);
		$expire = time() + 99999999;
		$domain = ($_SERVER['HTTP_HOST'] != 'localhost') ? $_SERVER['HTTP_HOST'] : false; // make cookies work with localhost
		setcookie('bigfa_ding_'.$id,$id,$expire,'/',$domain,false);
		if (!$bigfa_raters || !is_numeric($bigfa_raters)) {
			update_post_meta($id, 'bigfa_ding', 1);
		}else {
			update_post_meta($id, 'bigfa_ding', ($bigfa_raters + 1));
		}   
		echo get_post_meta($id,'bigfa_ding',true);    
    }     
    die;
}

<script type="text/javascript">
$(document).ready(function() { 
	$.fn.postLike = function() {
		if ($(this).hasClass('done')) {
			alert('您已赞过本博客');
			return false;
		} else {
			$(this).addClass('done');
			var id = $(this).data("id"),
			action = $(this).data('action'),
			rateHolder = $(this).children('.count');
			var ajax_data = {
				action: "bigfa_like",
				um_id: id,
				um_action: action
			};
			$.post("<?php bloginfo('url');?>/wp-admin/admin-ajax.php", ajax_data, function(data) {
				$(rateHolder).html(data);
			});
			return false;
		}
	};
	$(document).on("click", ".favorite", function() {
		$(this).postLike();
	});
}); 
</script>

<div class="post-like">
	<a href="javascript:;" data-action="ding" data-id="<?php the_ID(); ?>" class="favorite<?php if(isset($_COOKIE['bigfa_ding_'.$post->ID])) echo ' done';?>">喜欢 <span class="count">
	<?php 
		if( get_post_meta($post->ID,'bigfa_ding',true) ){            
			echo get_post_meta($post->ID,'bigfa_ding',true);
		} else {
			echo '0';
		}
	?></span>
	</a>
 </div>

.post-like{text-align:center;padding:10px}
.post-like a{ background-color:#21759B;border-radius: 3px;color: #FFFFFF;font-size: 12px;padding: 5px 10px;text-decoration: none;outline:none}
.post-like a.done, .post-like a:hover{background-color:#eee;color:#21759B;} 
.post-like a.done{cursor:not-allowed}