Edit in JSFiddle

var connection = $.hubConnection("http://signalrfiddle.cloudapp.net");

var echo = connection.createHubProxy("echo");

echo.on("Receive", function (val) {
    $("#list").append("<li>" + val + "</li>");
});

$("#send").click(function () {
    echo.invoke("Send", $("#message").val());
    
    $("#message").val("");
});

connection.start();

<input type="text" id="message" />
<input type="button" id="send" value="send" />

<ul id="list"></ul>