private void btnAddGV_Click(object sender, EventArgs e)
{
dialogGV d = new dialogGV();
d.type = "add";
d.maKhoa = txtMAK.Text;
d.ShowDialog();
reloadData();
}
private void btnSuaGV_ItemClick(object sender, DevExpress.XtraBars.ItemClickEventArgs e)
{
var positionGiaoVien = gvGV.FocusedRowHandle;
String idGV = txtMAGV.Text;
dialogGV d = new dialogGV();
d.idGV = idGV;
d.type = "edit";
d.ShowDialog();
reloadData();
}