Untitled

<body>
        <script>
            var Socket = new WebSocket("ws://localhost:778");

            Socket.onopen = function() {
                alert("Connection established");
            };
            Socket.onclose = function(event) {
                if (event.wasClean) {
                   alert('Connection closed clean');
                }
                else {
                   alert('Connection aborted'); // например, "убит" процесс сервера
                }
                alert('Code ' + event.code + ' Reason ' + event.reason);
            };

            Socket.onmessage = function(event) {
                alert("Data received " + event.data);
            };

            Socket.onerror = function(error) {
                alert("Error " + error.message);
            };
        </script>
    </body>