private void cboChonlop_SelectedIndexChanged(object sender, EventArgs e)
{
DataTable tbl = new DataTable();
rptBaocao rptReport = new rptBaocao();
string Malop = "";
Malop = cboChonlop.SelectedValue.ToString();
tbl = obj.GetDataTableReport(Malop);
rptReport.SetDataSource(tbl);
rptReport.Refresh();
crvReport.ReportSource = rptReport;
}