public int CreatGroup(List <string> users, string name)
        {
            UserDAL    userdal = new UserDAL();
            List <int> userid  = new List <int>();

            foreach (string username in users)
            {
                User tempuser = new User();
                tempuser = userdal.GetUserByLoginName(username);
                userid.Add(tempuser.Id);
            }
            GroupDAL groupdal = new GroupDAL();
            int      groupid  = groupdal.AddGroup(name);

            foreach (int id in userid)
            {
                if (groupdal.AddUserToGroup(id, groupid) < 0)
                {
                    return(-1);
                }
            }
            return(groupid);
        }