Javascript &引用；“长轮询”；模拟占用整个网页 简要概述

我有一个基于回合的web应用程序，每个回合都有60秒的限制，除非他们在60秒之前结束回合，然后下一个用户的回合开始

它的工作原理是通过

while

语句防止在PHP页面上生成数据，该语句检查新数据，如果存在则生成，如果不存在则休眠并重置：

while($olddata === $newdata){
    sleep(2);
    /* get new data and repeat */
}

我从这些问题中得到了这个概念：

问题 但是，一旦调用开始，页面就会变得相对无响应；在超时完成或收到新数据之前，执行一些简单的操作（如刷新页面）将不起作用

如何配置此代码，使页面在等待新数据时保持响应

AJAX/jQuery代码 PHP代码

---

如果您使用
session\u start（）
打开会话，最好在开始等待之前使用
session\u write\u close（）
将其关闭，否则在所有其他请求中都会阻止对会话的访问

<?php

session_start();
require_once("../config.php");
require_once("classes.php");
require_once("functions.php");

$postedID = $_POST["currID"];
$draft = new Draft($user->getLeagueID());
$currID = $draft->getCurrDraftRow();

//This is the "long polling" simulation...
//the AJAX callback won't produce any information
//until the current ID is different to the ID
//on the page with the AJAX post function
while($currID == $postedID){
    session_write_close(); //added
    sleep(2);
    session_start(); //if needed, doesn't look like it is though
    $currID = $draft->getCurrDraftRow();
}

/* Get all the data - redacted because it's not important (and it works) */

//Output all the data as one JSON object
exit(json_encode(array($nid, $ndeadline, $nuserid, $fteam, $fdraft)));

session\u write\u close（）很可能是您的问题。我会把它放在while循环之前，就像变量之后一样。另见此评论。
<?php

session_start();
require_once("../config.php");
require_once("classes.php");
require_once("functions.php");

$postedID = $_POST["currID"];
$draft = new Draft($user->getLeagueID());
$currID = $draft->getCurrDraftRow();

//This is the "long polling" simulation...
//the AJAX callback won't produce any information
//until the current ID is different to the ID
//on the page with the AJAX post function
while($currID == $postedID){
    sleep(2);
    $currID = $draft->getCurrDraftRow();
}

/* Get all the data - redacted because it's not important (and it works) */

//Output all the data as one JSON object
exit(json_encode(array($nid, $ndeadline, $nuserid, $fteam, $fdraft)));

<?php

session_start();
require_once("../config.php");
require_once("classes.php");
require_once("functions.php");

$postedID = $_POST["currID"];
$draft = new Draft($user->getLeagueID());
$currID = $draft->getCurrDraftRow();

//This is the "long polling" simulation...
//the AJAX callback won't produce any information
//until the current ID is different to the ID
//on the page with the AJAX post function
while($currID == $postedID){
    session_write_close(); //added
    sleep(2);
    session_start(); //if needed, doesn't look like it is though
    $currID = $draft->getCurrDraftRow();
}

/* Get all the data - redacted because it's not important (and it works) */

//Output all the data as one JSON object
exit(json_encode(array($nid, $ndeadline, $nuserid, $fteam, $fdraft)));