非插件实现emlog博客文章点赞功能

<?php //点赞
function syzan(){
$DB = MySql::getInstance();
if($DB->num_rows($DB->query("show columns from ".DB_PREFIX."blog like 'slzan'")) == 0){
$sql = "ALTER TABLE ".DB_PREFIX."blog ADD slzan int unsigned NOT NULL DEFAULT '0'";
$DB->query($sql);
}
}
syzan();
function update($logid){
$logid = intval($_POST['id']);
$DB = Database::getInstance();
$DB->query("UPDATE " . DB_PREFIX . "blog SET slzan=slzan+1 WHERE gid=$logid");
setcookie('slzanpd_'. $logid, 'true', time() + 31536000);
}
function lemoninit() {
if( @$_POST['plugin'] == 'slzanpd' &&@$_POST['action'] == 'slzan' &&isset($_POST['id'])){
$id = intval($_POST['id']);
header("Access-Control-Allow-Origin: *");
update($id);echo getnum($id);die;
}
}
lemoninit();
function getnum($id){
static $arr = array();
$DB = Database::getInstance();
if(isset($arr[$logid])) return $arr[$logid];
$sql = "SELECT slzan FROM " . DB_PREFIX . "blog WHERE gid=$id";
$res = $DB->query($sql);
$row = $DB->fetch_array($res);
$arr[$id] = intval($row['slzan']);
return $arr[$id];
}
?>

<script type="text/javascript">
$(document).on('click', '.slzanpd', function() {
var a = $(this),
id = a.data('slzanpd');
if (slzanpd_check(id)) {
alert('您已赞过本文！');
} else {
$.post('', {
plugin: 'slzanpd',
action: 'slzan',
id: id
},
function(b) {
a.find('u').html(b);
slzanpd_(a);
});
}
});
function slzanpd_check(id) {
return new RegExp('slzanpd_' + id + '=true').test(document.cookie);
}
$('[data-slzanpd]').each(function() {
var a = $(this),
id = a.data('slzanpd');
if (slzanpd_check(id)) {
slzanpd_(a);
} else {
a.attr('title', '给舍力来点动力吧！')
}
});
function slzanpd_(a) {
a.css('cursor', 'not-allowed').attr('title', '您已赞过本文！');
}
</script>

<div class="ding">
<a class="slzanpd" data-slzanpd="<?php echo $logData['logid'];?>" title="喜欢这篇文章就赞一个吧！">赞（<?php echo(isset($logData['slzan'])?$logData['slzan']:getnum($logData['logid']));?>次）</a>
</div>

.ding {overflow:hidden; font-size:14px;}
.ding a {display:block; float:left; background-color:#1F90DE; color:#fff; border-radius:3px; padding:5px 30px; cursor:pointer;}
.ding a:hover {color:#fff;}