SetSessionIdIfNotPreviouslySet.cs

/// <summary>
/// Sets the session identifier if not previously set.
/// </summary>
/// <param name="context">Context.</param>
/// <param name="sid">Sid.</param>
static void SetSessionIdIfNotPreviouslySet(HttpContextBase context, 
                                           string sid)
{
  SetCookie(context, "sid", 
            string.IsNullOrEmpty(sid) ? Guid.NewGuid().ToString() : sid);
}