function unfollowchannel(){
if ($_SESSION['user']->isAnon())
return array("ok"=>false, "error"=>"you have to login");
$channel = new Channel();
if (!isset($_GET['channelid_unfollowchannel']))
return array("ok"=>false, "error"=>"no id");
$channel->setId($_GET['channelid_unfollowchannel']);
if ($channel->getUser()->getId()==$_SESSION['user']->getId())
return array("ok"=>false, "error"=>"channel owner cant unfollow");
if ($channel->unfollow())
return array("ok"=>true, "error"=>"");
else
return array("ok"=>false, "error"=>"cant unfollow");
}