private void btnDeleteWorker_Click(object sender, EventArgs e)
        {
            if (dgvWorkingPersonnel.CurrentRow != null)
            {
                //var result = from client in db.Client
                //             select client
                long             id = Convert.ToInt64(dgvWorkingPersonnel.CurrentRow.Cells[0].Value);
                WorkingPersonnel workingPersonnel = db.WorkingPersonnel.Where(o => o.IDworker == id).FirstOrDefault();

                db.WorkingPersonnel.Remove(workingPersonnel);
                db.SaveChanges();
            }
        }
        private void btnAddWorker_Click(object sender, EventArgs e)
        {
            WorkingPersonnel working = new WorkingPersonnel
            {
                IDworker       = 2,
                FamilyName     = "Ванов",
                Name           = "Вася",
                Patronymic     = "ХАХАХА",
                Specialization = "Roflanebalo"
            };

            db.WorkingPersonnel.Add(working);
            db.SaveChanges();
        }