public void DeleteSalerPayment(SalerPayment payment)
 {
     payment = _db.SalerPayments.FirstOrDefault(cust => cust.SalerPaymentId == payment.SalerPaymentId);
     if (payment != null)
     {
         _db.Entry(payment).State = EntityState.Deleted;
         _db.SaveChanges();
     }
     else
     {
         throw new Exception("SalerPayment Id cannot be found");
     }
 }
 public void UpdateSalerPayment(SalerPayment payment)
 {
     payment = _db.SalerPayments.FirstOrDefault(cust => cust.SalerPaymentId == payment.SalerPaymentId);
     _db.Entry(payment).State = EntityState.Modified;
     _db.SaveChanges();
 }
 public void AddSalerPayment(SalerPayment payment)
 {
     _db.SalerPayments.Add(payment);
     _db.SaveChanges();
 }