因此，Idea位于setInterval和Sockets的后面，大多数浏览器都支持setInterval，几乎每个浏览器都支持javascript WbsocketApi。
简要概述：setInterval（）-当您的计算机处于睡眠/暂停/休眠模式时，将暂停此函数行为；在唤醒模式时，它将恢复自身的状态。
以下代码首先执行以下操作（也许同时），但它启动php server_socket来监听连接，
比javascript websocket api每2秒发送一次当前时间戳（以Unix时间戳毫秒为单位），您可以将1秒钟取决于您。
在该php服务器套接字获取此时间后，检查是否有与上次比较的时间，第一次实例化代码时php没有与上一次的时间比较的内容与从javascript websocket发送的时间进行比较，因此php什么都不做，只是将这段时间保存在名为“ prev_time”的会话中，并等待从JavaScript套接字接收另一个时间数据，因此这里开始第二个周期。当php服务器从javascript WebsocketApi中获取新的时间数据时，它会检查它是否有与上次时间类似的东西来与这个新接收的时间数据进行比较，这意味着php会检查是否存在名为“ prev_time”的会话，因为我们在第二个周期中php发现它存在，抓住它的价值，然后做$diff = $new_time - $prev_time，$ diff为2秒或2000毫秒，因为请记住我们的setInterval周期每2秒发生一次，而我们发送的时间格式以毫秒为单位，
比PHP检查if($diff<3000)差异是否小于3000，如果它知道用户处于活动状态，那么您也可以根据需要操作此秒，我选择3000，因为网络中可能存在的延迟几乎是不可能的，但是您知道我总是谨慎它涉及网络，因此让我们继续，当php确定用户处于活动状态时，php只是重置“ prev_time”会话，其值$new_time是新接收的，并且仅出于测试目的，它将消息发送回javascript套接字，
但是如果$diff大于3000，则表示某件事使我们的setInterval暂停了，并且只能发生，我想您已经知道我在说什么，因此按照else（if($diff<3000)）的逻辑，您可以通过销毁特定会话来注销用户，如果要重定向，您可以将一些文本发送到javacript套接字并创建一个将window.location = "/login"根据文本执行的逻辑，这就是代码：
首先，它是index.html文件，仅用于加载javascript：
<html>
<body>
<div id="printer"></div>
<script src="javascript_client_socket.js"></script>
</body>
</html>
那么它是javascript代码，编码不是很漂亮，但是您可以弄清楚它们的重要性：
var socket = new WebSocket('ws://localhost:34237'); // connecting to socket
// Open the socket
socket.onopen = function(event) { // detecting when connection is established
setInterval(function(){ //seting interval for 2 seconds
var date = new Date(); //grabing current date
var nowtime = Date.parse(date); // parisng it in miliseconds
var msg = 'I am the client.'; //jsut testing message
// Send an initial message
socket.send(nowtime); //sending the time to php socket
},2000);
};
// Listen for messages
socket.onmessage = function(event) { //print text which will be sent by php socket
console.log('php: ' + event.data);
};
// Listen for socket closes
socket.onclose = function(event) {
console.log('Client notified socket has closed', event);
};
现在这里是php代码的一部分，不要担心也有完整的代码，但这部分实际上就是上述工作，您也会遇到其他功能，但是它们是用于解码和使用javascript套接字的，所以这是正确的事情在这里阅读评论，它们很重要：
<?php
$decoded_data = unmask($data /* $data is actual data received from javascript socket */); //grabbing data and unmasking it | unmasking is for javascript sockets don't mind this
print("< ".$decoded_data."\n");
$response = strrev($decoded_data);
$jsTime = (int) $decoded_data; /* time sent by javascript in MILISECONDS IN UNIX FORMAT */
if (isset($_SESSION['prev_time'])) { /** check if we have stored previous time in the session */
$prev_time = (int) $_SESSION['prev_time']; /** grabbing the previous time from session */
$diff = $jsTime-$prev_time; /** getting the difference newly sent time and previous time by subtracting */
print("$jsTime - $prev_time = $diff"); /** printing the difference */
if($diff<3000){ /** checking if difference is less than 3 second if it is it means pc was not at sleep
*** you can manipulate and have for example 1 second = 1000ms */
socket_write($client,encode("You are active! your pc is awakend"));
$_SESSION['prev_time'] = $jsTime; /** saving newly sent time as previous time for future testing whcih will happen in two seconds in our case*/
}else { /** if it is more than 3 seconds it means that javascript setInterval function was paused and resumed after 3 seconds
** So it means that it was at sleep because when your PC is at sleep/suspended/hibernate mode setINterval gets pauesd */
socket_write($client,encode("You are not active! your pc is at sleep"));
$_SESSION['prev_time'] = $jsTime;
}
}else { /** if we have not saved the previous time in session save it */
$_SESSION['prev_time'] = $jsTime;
}
print_r($_SESSION);
?>
这是php的完整代码：
<?php
//Code by: Nabi KAZ <www.nabi.ir>
session_abort();
// set some variables
$host = "127.0.0.1";
$port = 34237;
date_default_timezone_set("UTC");
// don't timeout!
set_time_limit(0);
// create socket
$socket = socket_create(AF_INET, SOCK_STREAM, 0)or die("Could not create socket\n");
// bind socket to port
$result = socket_bind($socket, $host, $port)or die("Could not bind to socket\n");
// start listening for connections
$result = socket_listen($socket, 20)or die("Could not set up socket listener\n");
$flag_handshake = false;
$client = null;
do {
if (!$client) {
// accept incoming connections
// client another socket to handle communication
$client = socket_accept($socket)or die("Could not accept incoming connection\n");
}
$bytes = @socket_recv($client, $data, 2048, 0);
if ($flag_handshake == false) {
if ((int)$bytes == 0)
continue;
//print("Handshaking headers from client: ".$data."\n");
if (handshake($client, $data, $socket)) {
$flag_handshake = true;
}
}
elseif($flag_handshake == true) {
/*
**** Main section for detectin sleep or not **
*/
if ($data != "") {
$decoded_data = unmask($data /* $data is actual data received from javascript socket */); //grabbing data and unmasking it | unmasking is for javascript sockets don't mind this
print("< ".$decoded_data."\n");
$response = strrev($decoded_data);
$jsTime = (int) $decoded_data; /* time sent by javascript in MILISECONDS IN UNIX FORMAT */
if (isset($_SESSION['prev_time'])) { /** check if we have stored previous time in the session */
$prev_time = (int) $_SESSION['prev_time']; /** grabbing the previous time from session */
$diff = $jsTime-$prev_time; /** getting the difference newly sent time and previous time by subtracting */
print("$jsTime - $prev_time = $diff"); /** printing the difference */
if($diff<3000){ /** checking if difference is less than 3 second if it is it means pc was not at sleep
*** you can manipulate and have for example 1 second = 1000ms */
socket_write($client,encode("You are active! your pc is awakend"));
$_SESSION['prev_time'] = $jsTime; /** saving newly sent time as previous time for future testing whcih will happen in two seconds in our case*/
}else { /** if it is more than 3 seconds it means that javascript setInterval function was paused and resumed after 3 seconds
** So it means that it was at sleep because when your PC is at sleep/suspended/hibernate mode setINterval gets pauesd */
socket_write($client,encode("You are not active! your pc is at sleep"));
$_SESSION['prev_time'] = $jsTime;
}
}else { /** if we have not saved the previous time in session save it */
$_SESSION['prev_time'] = $jsTime;
}
print_r($_SESSION);
/*
**** end of Main section for detectin sleep or not **
*/
}
}
} while (true);
// close sockets
socket_close($client);
socket_close($socket);
$client = null;
$flag_handshake = false;
function handshake($client, $headers, $socket) {
if (preg_match("/Sec-WebSocket-Version: (.*)\r\n/", $headers, $match))
$version = $match[1];
else {
print("The client doesn't support WebSocket");
return false;
}
if ($version == 13) {
// Extract header variables
if (preg_match("/GET (.*) HTTP/", $headers, $match))
$root = $match[1];
if (preg_match("/Host: (.*)\r\n/", $headers, $match))
$host = $match[1];
if (preg_match("/Origin: (.*)\r\n/", $headers, $match))
$origin = $match[1];
if (preg_match("/Sec-WebSocket-Key: (.*)\r\n/", $headers, $match))
$key = $match[1];
$acceptKey = $key.'258EAFA5-E914-47DA-95CA-C5AB0DC85B11';
$acceptKey = base64_encode(sha1($acceptKey, true));
$upgrade = "HTTP/1.1 101 Switching Protocols\r\n".
"Upgrade: websocket\r\n".
"Connection: Upgrade\r\n".
"Sec-WebSocket-Accept: $acceptKey".
"\r\n\r\n";
socket_write($client, $upgrade);
return true;
} else {
print("WebSocket version 13 required (the client supports version {$version})");
return false;
}
}
function unmask($payload) {
$length = ord($payload[1]) & 127;
if ($length == 126) {
$masks = substr($payload, 4, 4);
$data = substr($payload, 8);
}
elseif($length == 127) {
$masks = substr($payload, 10, 4);
$data = substr($payload, 14);
}
else {
$masks = substr($payload, 2, 4);
$data = substr($payload, 6);
}
$text = '';
for ($i = 0; $i < strlen($data); ++$i) {
$text .= $data[$i] ^ $masks[$i % 4];
}
return $text;
}
function encode($text) {
// 0x1 text frame (FIN + opcode)
$b1 = 0x80 | (0x1 & 0x0f);
$length = strlen($text);
if ($length <= 125)
$header = pack('CC', $b1, $length);
elseif($length > 125 && $length < 65536)$header = pack('CCS', $b1, 126, $length);
elseif($length >= 65536)
$header = pack('CCN', $b1, 127, $length);
return $header.$text;
}
注意：
$new_time变量$jsTime在代码中
创建文件夹，然后将其复制并粘贴到文件中，然后使用以下命令运行php socket：php -f server_socket.php进入本地主机并对其进行测试，打开控制台以查看消息，该消息将显示“您处于活动状态”或“您处于非活动状态” （当您从睡眠中回来时）；您的可执行文件将在用户进入睡眠状态而不是在睡眠状态时发生，因为此时所有内容都缓存在pagefile（windows）或swap（linux）中