public void Delete(Product entity)
 {
     using (var _context = new MAppDataContext())
     {
         var deleteEntity = _context.Entry(entity);
         deleteEntity.State = EntityState.Deleted;
         _context.SaveChanges();
     }
 }
 public void Update(Product entity)
 {
     using (var _context = new MAppDataContext())
     {
         var updatedEntity = _context.Entry(entity);
         updatedEntity.State = EntityState.Modified;
         _context.SaveChanges();
     }
 }
 public void Add(Product entity)
 {
     using (var _context = new MAppDataContext())
     {
         var addEntity = _context.Entry(entity);
         addEntity.State = EntityState.Added;
         _context.SaveChanges();
     }
 }