void LoadData()
{
this.dataTable = BLAcc.getStaffDHaveAcc();
this.dgvTaiKhoan.DataSource = dataTable;
this.cbBoxSelect.SelectedIndex = 2;
this.cbBoxIDTen.SelectedIndex = 2;
this.txtUsername.ResetText();
this.txtUsername.Enabled = false;
this.txtPassword.ResetText();
this.txtPassword.Enabled = false;
this.btnThem.Enabled = false;
this.btnHuy.Enabled = false;
this.btnLuu.Enabled = false;
this.cbChucvu.Enabled = false;
DgvTaiKhoan_CellClick(null, null);
}