public string DeleteUserGroup(string id) { if (string.IsNullOrWhiteSpace(id)) { throw new Exception("No user group id"); } else { int?ugId = Convert.ToInt32(id); if (ugId.HasValue) { UserRole userRole = null; using (var proxy = new UserProxy()) { userRole = proxy.GetUserGroupById(ugId.Value); if (userRole != null) { if (userRole.Users != null && userRole.Users.Count > 0) { proxy.DeleteUserGroup(ugId.Value); return(string.Empty); } else { // Cannot delete return("Cannot delete, has user"); } } else { throw new Exception("Invalid user id"); } } } else { throw new Exception("Invalid user id"); } } }