来自mysql的长轮询信息不起作用

将您的poll.php文件中的代码更改为以下内容：

<?phpinclude 'db.php';$old_msg_id = $_GET['old_msg_id']; $result = mysql_query("SELECt id FROM chatpoll ORDER BY id DESC LIMIT 1");while($row = mysql_fetch_array($result)){    $last_msg_id = $row['id']; }while($last_msg_id <= $old_msg_id){    usleep(1000);    clearstatcache();    $result = mysql_query("SELECt id FROM chatpoll ORDER BY id DESC LIMIT 1");    while($row = mysql_fetch_array($result))    {        $last_msg_id = $row['id'];    }}$response = array();$response['msg'] = 'new';$response['old_msg_id'] = $last_msg_id;echo json_enpre($response);?>