export delphi stringgrid to excel

Question

I'm trying to export data from a stringgrid in delphi 7 to microsoft excel. I have been using this code to do it:

  objExcel := TExcelApplication.Create(nil);
  objExcel.Visible[LOCALE_USER_DEFAULT] := true;
  objWB := objExcel.workbooks.add(null,LOCALE_USER_DEFAULT);
  lineNumber := 1;

  for i:=1 to stringgrid1.rowcount-1 do begin
    for j:=0 to stringgrid1.ColCount-1 do begin
      objWB.Worksheets.Application.Cells.Item[i+lineNumber,j+1] := ''''+stringgrid1.Cells[j,i];
    end;
  end;

but when the data is big, it takes a very long time to finish. is there other faster way to export data from delphi 7 stringgrid to excel?

Answer 1

procedure WriteToExcel();
var
  txt : TextFile;
  Str : string;
  i : integer;
begin
  try
    SaveDialog1.FileName := 'excelFile('+FormatDateTime('yyyy-dd-mm hh-nn-ss' ,(Now))+')';
    if SaveDialog1.Execute then
      begin
        AssignFile(txt, SaveDialog1.FileName+'.csv');
        try
          if FileExists(SaveDialog1.FileName) then
            Append(txt)
          else
            ReWrite(txt);
          Str := 'title1, title2, title3, title4, title5';
          WriteLn(txt, Str);
          ShowQuery.First();
          for i:=1 to StringGrid1.RowCount do
            begin
              Str := StringGrid1.Cols[i][1] + ',';
              Str := Str + StringGrid1.Cols[i][2] + ',';
              Str := Str + StringGrid1.Cols[i][3] + ',';
              Str := Str + StringGrid1.Cols[i][4] + ',';
              Str := Str + StringGrid1.Cols[i][5];
              WriteLn(txt,  Str);
            end;
        finally
          CloseFile(txt);
        end;
      end;
  except

  end;
end;

Answer 2

The problem is that you are calling the Excel object for every cell; this is a slow operation at the best of times, so doing this for a large number of cells is going to take a long time. I had a case of this not so long ago: 4000 rows with 9 columns took about 44 seconds to transfer to Excel.

My current solution involves creating a csv file then importing that csv into Excel.

const
 fn = 'c:\windows\temp\csv.csv';

var
 csv: tstringlist;
 row, col: integer;
 s: string;

begin
 csv:= tstringlist.create;
 for row:= 1 to stringgrid1.rowcount do 
  begin
   s:= '';
   for col:= 0 to stringgrid1.ColCount-1 do 
    s:= s + stringgrid1.Cells[col, row-1] + ',';
   csv.add (s)
  end;

 csv.savetofile (fn);
 csv.free;

 objExcel := TExcelApplication.Create(nil);
 objExcel.workbooks.open (fn);
 deletefile (fn);
end;

Another way comes from Mike Shkolnik which I am quoting as is:

var
 xls, wb, Range: OLEVariant;
 arrData: Variant;

begin
{create variant array where we'll copy our data}
 arrData := VarArrayCreate([1, yourStringGrid.RowCount, 1, yourStringGrid.ColCount], varVariant);

 {fill array}
 for i := 1 to yourStringGrid.RowCount do
  for j := 1 to yourStringGrid.ColCount do
   arrData[i, j] := yourStringGrid.Cells[j-1, i-1];

 {initialize an instance of Excel}
 xls := CreateOLEObject('Excel.Application');

 {create workbook}
 wb := xls.Workbooks.Add;

 {retrieve a range where data must be placed}
 Range := wb.WorkSheets[1].Range[wb.WorkSheets[1].Cells[1, 1],
                              wb.WorkSheets[1].Cells[yourStringGrid.RowCount, yourStringGrid.ColCount]];

 {copy data from allocated variant array}
 Range.Value := arrData;

 {show Excel with our data}
 xls.Visible := True;
end;

I suggest that you try both methods and see which is faster for your purposes.

Answer 3

The quickest way is to use an array of Variant,and just pass the entire array to Excel:

uses OleAuto;

var
  xls, wb, Range: OLEVariant;
  arrData: Variant;
  RowCount, ColCount, i, j: Integer;
begin
  {create variant array where we'll copy our data}
  RowCount := StringGrid1.RowCount;
  ColCount := StringGrid1.ColCount;
  arrData := VarArrayCreate([1, RowCount, 1, ColCount], varVariant);

  {fill array}
  for i := 1 to RowCount do
    for j := 1 to ColCount do
      arrData[i, j] := StringGrid1.Cells[j-1, i-1];

  {initialize an instance of Excel}
  xls := CreateOLEObject('Excel.Application');

  {create workbook}
  wb := xls.Workbooks.Add;

  {retrieve a range where data must be placed}
  Range := wb.WorkSheets[1].Range[wb.WorkSheets[1].Cells[1, 1],
                                  wb.WorkSheets[1].Cells[RowCount, ColCount]];

  {copy data from allocated variant array}
  Range.Value := arrData;

  {show Excel with our data}
  xls.Visible := True;
end;