I am making simple chat on my webpage. I want to save selected user ( value) to cookie to keep user selected after reload.

My code:

<div id="chatContainer" name="chatCointainer">
<select onChange="clearAndRefresh()" id="selectUser" name="selectUser" size="24">
    <option selected="selected" value="1">User1</option>
    <option value="2">User2</option>
    <option value="3">User3</option>
    <option value="4">User4</option>
</select>
</div>

<script type="text/javascript">
    window.setInterval(refreshOnly, 5000);

    var saveclass = null;

    function saveUserSelection() {

        var sel = document.getElementById('selectUser');
        var cookieValue = document.getElementById('selectUser').value;

        saveclass = saveclass ? saveclass : document.body.className;
        document.body.className = saveclass + ' ' + sel.value;

        setCookie('userselection', cookieValue, 365);
    }

    function setCookie(cookieName, cookieValue, nDays) {

        var today = new Date();
        var expire = new Date();

        if (nDays == null || nDays == 0)
            nDays = 1;

        expire.setTime(today.getTime() + 3600000 * 24 * nDays);
        document.cookie = cookieName + "=" + escape(cookieValue) + ";expires=" + expire.toGMTString();
    }

    function readCookie(name) {

        var nameEQ = name + "=";
        var ca = document.cookie.split(';');

        for (var i = 0; i < ca.length; i++) {
            var c = ca[i];
            while (c.charAt(0) == ' ') c = c.substring(1, c.length);
            if (c.indexOf(nameEQ) == 0) return c.substring(nameEQ.length, c.length);
        }
        return null;
    }

    function getUserSelectionFromCookie() {

        var userSelect = document.getElementById('selectUser');
        var selectedUser = readCookie('userselection');

        userSelect.value = selectedUser;
        saveclass = saveclass ? saveclass : document.body.className;
        document.body.className = saveclass + ' ' + selectedUser;
    }


    function showUnreadMessages() {
        $.ajaxSetup({ cache: false });
        $("#chatContainer").load(location.href + " #chatContainer");
    }

    function clearAndRefresh() {
        saveUserSelection();
        $("#userMessage").val("");
    }

    function refreshOnly() {
        saveUserSelection();
        showUnreadMessages();
        getUserSelectionFromCookie();
    }
</script>

My problem is that after

$.ajaxSetup({ cache: false });
$("#chatContainer").load(location.href + " #chatContainer");

there is no selected value.

Please help, regards.