while not XLDataSet.Eof do begin
(FBuff as TxlBuffer).GetRecord(Self, FRows);
FRecordCount := FRecordCount + 1;
{$IFDEF XLR_VCL}
(Report as TxlReport).DoOnProgress2(Self as TxlDataSource, FRecordCount);
{$ENDIF}
{$IFDEF XLR_TRIAL}
{$I xlDoRestrict5.inc}
{$ENDIF}
XLDataSet.Next;
Report.CheckBreak;
end;

function TxlVarBuffer.CheckLimits(const Immediately: boolean; Source: TxlExcelDataSource): boolean;
var
  IRange: IxlRange;
  Formulas: OLEVariant;
  i, j: integer ;
begin
  Result := (RowCount >= xlrMaxVarRowCount) or Immediately;
  if Assigned(Source) and Result and (RowCount > 0) and (not _VarIsEmpty(FBuff)) then begin
    if Source.RangeType <> rtRange then
      IRange := InsertBlankRows(Root.IRange.Rows.Count, RowCount, Root.ColCount, Root.ITempSheet, Root.IRange)
    else begin
      IRange := InsertBlankRows2(Root.IRange.Rows.Count, RowCount, Root.ColCount, Root.ITempSheet, Root.IRange, Source.FIUnMergedRows);
    Formulas := VarArrayCreate([1, RowCount, 1, Root.ColCount], varVariant);
    for i := 1 to RowCount do
      for j := 1 to Root.ColCount do
        Formulas[i, j] := FBuff[j, i];
        //IRange.Cells.Item[i, j].Value  := FBuff[j, i]; //лучше но медленно

    IRange.Value := Formulas; // replace IRange.Formula := Formulas (rc1)

    if not Immediately then
      StartBuffer;
  end;
end;

procedure TxlVarBuffer.StartBuffer;
begin
  FBuff := VarArrayCreate([1, Root.ColCount, 1, 1], varVariant)
end;

function TxlVarBuffer.CheckLimits(const Immediately: boolean; Source: TxlExcelDataSource): boolean;
var
  //IRange: IxlRange;
  IRange: Variant;
...