/// <summary>
 /// insert a record into table MATHANG- increament number of MATHANG
 /// </summary>
 /// <param name="tenhang"></param>
 /// <param name="tendvt"></param>
 /// <param name="dongia"></param>
 /// <returns></returns>
 public bool InsertMATHANG(string tenhang, int madvt, int dongia)
 {
     using (QLDLEntities db = new QLDLEntities())
     {
         MATHANG mh = new MATHANG();
         mh.TENHANG = tenhang;
         mh.MADVT   = madvt;
         mh.DONGIA  = dongia;
         db.MATHANGs.Add(mh);
         db.SaveChanges();
         return(true);
     }
 }
 /// <summary>
 /// delete a record into table MATHANG - descreament number of MATHANG
 /// </summary>
 /// <param name="mamh"></param>
 /// <returns></returns>
 public bool DeleteMATHANG(int mamh)
 {
     using (QLDLEntities db = new QLDLEntities())
     {
         if (db.CTPXes.Where(p => p.MAHANG == mamh).Count() <= 0)
         {
             MATHANG mh = db.MATHANGs.Where(p => p.MAHANG == mamh).Single();
             db.MATHANGs.Remove(mh);
             db.SaveChanges();
             return(true);
         }
         return(false);
     }
 }