وب‌سوکت

DOCTYPE html>  <meta charset="utf-8"/>  <title>WebSocket Test</title>  <script language="javascript" type="text/javascript">    var wsUri = "ws://echo.websocket.org/";   var output;    function init()   {     output = document.getElementById("output");     testWebSocket();   }    function testWebSocket()   {     websocket = new WebSocket(wsUri);     websocket.onopen = function(evt) { onOpen(evt) };     websocket.onclose = function(evt) { onClose(evt) };     websocket.onmessage = function(evt) { onMessage(evt) };     websocket.onerror = function(evt) { onError(evt) };   }    function onOpen(evt)   {     writeToScreen("CONNECTED");     doSend("WebSocket rocks");   }    function onClose(evt)   {     writeToScreen("DISCONNECTED");   }    function onMessage(evt)   {     writeToScreen('RESPONSE: ' + evt.data+'');     websocket.close();   }    function onError(evt)   {     writeToScreen('ERROR: ' + evt.data);   }    function doSend(message)   {     writeToScreen("SENT: " + message);     websocket.send(message);   }    function writeToScreen(message)   {     var pre = document.createElement("p");     pre.style.wordWrap = "break-word";     pre.innerHTML = message;     output.appendChild(pre);   }    window.addEventListener("load", init, false);  </script>