get userroles in javascrips

 guid2.replace(/[{}]/g, "").toLowerCase();
function GetRequestObject() {
    if (window.XMLHttpRequest) {
        return new window.XMLHttpRequest;
    }
    else {
        try {
            return new ActiveXObject("MSXML2.XMLHTTP.3.0");
        }
        catch (ex) {
            return null;
        }
    }
}

function UserHasRoleS(roleName) {

    var serverUrl =GetServerURL();
    var UserBUId = XrmServiceToolkit.Soap.GetCurrentUserBusinessUnitId();

    var oDataEndpointUrl = serverUrl + "/XRMServices/2011/OrganizationData.svc/";
    oDataEndpointUrl += "RoleSet?$top=1&$filter=Name eq '" + roleName + "' and BusinessUnitId/Id eq (guid'" + Id + "')";

    var service = GetRequestObject();
    if (service != null) {
        service.open("GET", oDataEndpointUrl, false);
        service.setRequestHeader("X-Requested-Width", "XMLHttpRequest");
        service.setRequestHeader("Accept", "application/json, text/javascript, */*");
        service.send(null);
        var requestResults = eval('(' + service.responseText + ')').d;
        if (requestResults != null && requestResults.results.length == 1) {
            var role = requestResults.results[0];
            var id = role.RoleId;
            var currentUserRoles = Xrm.Page.context.getUserRoles();
            for (var i = 0; i < currentUserRoles.length; i++) {
                var userRole = currentUserRoles[i];
                if (userRole=="admin") {
                    return true;
                }
            }
        }
    }
    return false;
}