private void cboNamHoc_SelectedIndexChanged(object sender, EventArgs e)
{
ComboboxLoad.Lop(cboLop, cboNamHoc, cboLoaiLop);
dgvKetQua.DataSource = null;
}
private void cboLoaiLop_LuaChon_SelectedIndexChanged(object sender, EventArgs e)
{
ComboboxLoad.Lop(cboLopHoc_LuaChon, cboNamHoc_LuaChon, cboLoaiLop_LuaChon);
dgvDanhSach.DataSource = null;
}