public void Delete(int id)
        {
            GroupLes gl = GetGroupLes(id);

            if (gl != null)
            {
                cont.GroupLesSet.Remove(gl);
                cont.SaveChanges();
            }
        }
        public GroupLes Add(short mo, short tu, short we, short th, short fr, short sa, Subject sub)
        {
            GroupLes gl = new GroupLes();

            gl.Mo      = mo;
            gl.Tu      = tu;
            gl.We      = we;
            gl.Th      = th;
            gl.Fr      = fr;
            gl.Sa      = sa;
            gl.Subject = sub;
            cont.GroupLesSet.Add(gl);
            cont.SaveChanges();
            return(gl);
        }
        public void Edit(int id, short mo, short tu, short we, short th, short fr, short sa, Subject sub)
        {
            GroupLes gl = GetGroupLes(id);

            if (gl != null)
            {
                gl.Mo      = mo;
                gl.Tu      = tu;
                gl.We      = we;
                gl.Th      = th;
                gl.Fr      = fr;
                gl.Sa      = sa;
                gl.Subject = sub;
                cont.SaveChanges();
            }
        }