private void dgvClassrooms_RowHeaderMouseDoubleClick(object sender, DataGridViewCellMouseEventArgs e) { int id = (int)dgvClassrooms.Rows[e.RowIndex].Cells[0].Value; selectedClassroom = dto.Get(id); txtClassroomName.Text = selectedClassroom.Name; numericCapacity.Value = selectedClassroom.Capacity; btnDelete.Visible = true; btnUpdate.Visible = true; }