public static void ExcelFileToDataTable(out DataTable dtData, string sFile, string sRequest)
        {
            DataSet dsData = new DataSet();
            const string provider = "Microsoft.ACE.OLEDB.12.0";
            string extProp = sFile.EndsWith(".xlsx", StringComparison.CurrentCulture) ? "Excel 12.0 Xml" : "Excel 8.0";
            string sConnStr = $"Provider={provider};Data Source={sFile};Extended Properties=\"{extProp};HDR=YES\";";

            using (OleDbConnection odcConnection = new OleDbConnection(sConnStr))
            {
                odcConnection.Open();
                if (sRequest.IndexOf("$SHEETS$", StringComparison.CurrentCulture) != -1)
                {
                    using (DataTable dtMetadata = odcConnection.GetOleDbSchemaTable(OleDbSchemaGuid.Tables, new object[4] { null, null, null, "TABLE" }))
                    {
                        for (int i = 0; i < dtMetadata.Rows.Count; i++)
                        {
                            if (dtMetadata.Rows["TABLE_NAME"].ToString().IndexOf("$", StringComparison.CurrentCulture) == -1)
                            {
                                dtMetadata.Rows.Remove(dtMetadata.Rows[i]);
                            }
                        }

                        foreach (DataRow drRow in dtMetadata.Rows)
                        {
                            string sLocalRequest = sRequest.Replace("$SHEETS$", String.Format("[{0}]", drRow["TABLE_NAME"]));
                            OleDbCommand odcCommand = new OleDbCommand(sLocalRequest, odcConnection);
                            using (OleDbDataAdapter oddaAdapter = new OleDbDataAdapter((OleDbCommand)odcCommand))
                            {
                                oddaAdapter.Fill(dsData);
                            }
                        }
                    }
                }
                else
                {
                    OleDbCommand odcCommand = new OleDbCommand(sRequest, odcConnection);
                    using (OleDbDataAdapter oddaAdapter = new OleDbDataAdapter(odcCommand))
                    {
                        oddaAdapter.Fill(dsData);
                    }
                }
                odcConnection.Close();
            }

            dtData = dsData.Tables[0];
        }