private void BtnExport_Click(object sender, EventArgs e) { ExportToExcel excel = new ExportToExcel(); string query = "SELECT * FROM dbo.NhanVien"; System.Data.DataTable data = DataProvider.Instance.ExecuteQuery(query); excel.ExportNhanVien(data, "Danh sach NV", "DANH SÁCH NHÂN VIÊN"); }