将dataset中的数据导出至Excel中而不需要安装MS Excel的方法(含UNICODE支持)
作者:互联网
偶尔做界面程序,需要一个导出Excel,而在客户端又不用安装MS Excel的方法,总结如下。
测试了两种方法,第一种方法如下(此方法支持UNICODE不存在问题):
参考:http://www.swissdelphicenter.ch/torry/showcode.php?id=1427
procedure DBGridToExcelADO(Query: TDataSet; FileName: string; SheetName: string); var cat: _Catalog; tbl: _Table; col: _Column; i: integer; ADOConnection: TADOConnection; ADOQuery: TADOQuery; begin if FileExists(FileName) then // It's better to delete the file first, or there may be a "external table is not in the expected format" error. by genispan DeleteFile(FileName); //WorkBook creation (database) cat := CoCatalog.Create; //cat._Set_ActiveConnection cat.Set_ActiveConnection('Provider=Microsoft.Jet.OLEDB.4.0; Data Source=' + FileName + ';Extended Properties=Excel 8.0'); //WorkSheet creation (table) tbl := CoTable.Create; tbl.Set_Name(SheetName); //Columns creation (fields) Query.First; with Query.Fields do begin for i := 0 to Count - 1 do begin col := nil; col := CoColumn.Create; with col do begin Set_Name(Query.Fields[i].FieldName); Set_Type_(adVarWChar); end; //add column to table tbl.Columns.Append(col, adVarWChar, 20); end; end; //add table to database cat.Tables.Append(tbl); col := nil; tbl := nil; cat := nil; ADOConnection := TADOConnection.Create(nil); ADOConnection.LoginPrompt := False; ADOConnection.ConnectionString := 'Provider=Microsoft.Jet.OLEDB.4.0; Data Source=' + FileName + ';Extended Properties=Excel 8.0'; ADOQuery := TADOQuery.Create(nil); ADOQuery.Connection := ADOConnection; ADOQuery.SQL.Text := 'Select * from [' + SheetName + '$]'; ADOQuery.Open; try with Query do begin First; while not Eof do begin ADOQuery.Append; with Query.Fields do begin ADOQuery.Edit; for i := 0 to Count - 1 do ADOQuery.FieldByName(Query.Fields[i].FieldName).AsString := FieldByName(Query.Fields[i].FieldName).AsString; ADOQuery.Post; end; Next; end; end; finally ADOQuery.Close; ADOConnection.Close; ADOQuery.Free; ADOConnection.Free; end; end;
第二种方法,此方法效率更高,但导出UNICODE字符串存在问题,如有高手看到可留言帮助解决下,以下为整理好了的pas单元源码:
unit uExcel; interface Uses DB, Classes, Dialogs,DBGrids,Controls; var CXlsBof: array[0..5] of Word = ($809, 8, 0, $10, 0, 0); //OPCode, size, codepage CXlsCodePage: array[0..2] of Word = ($0042, $0002, $04B0); CXlsEof: array[0..1] of Word = ($0A, 00); CXlsLabel: array[0..5] of Word = ($204, 0, 0, 0, 0, 0); CXlsNumber: array[0..4] of Word = ($203, 14, 0, 0, 0); CXlsRk: array[0..4] of Word = ($27E, 10, 0, 0, 0); CXlsBlank: array[0..4] of Word = ($201, 6, 0, 0, $17); Type TDS2Excel = Class(TObject) Private FCol: word; FRow: word; FDataSet: TDataSet; FDbGrid :TDbGrid; Stream: TStream; FWillWriteHead: boolean; FBookMark: TBookmark; procedure IncColRow; procedure WriteBlankCell; procedure WriteFloatCell(const AValue: Double); procedure WriteIntegerCell(const AValue: Integer); procedure WriteStringCell(const AValue: string); procedure WritePrefix; procedure WriteSuffix; procedure WriteTitle; procedure WriteDataCell; procedure Save2Stream(aStream: TStream); Public procedure Save2File(FileName: string; WillWriteHead: Boolean); procedure Save2Files(WillWriteHead: Boolean); Constructor Create(aDataSet: TDataSet;aDBGrid:TDBGrid); end; implementation uses SysUtils; Constructor TDS2Excel.Create(aDataSet: TDataSet;aDBGrid:TDBGrid); begin inherited Create; FDataSet := aDataSet; FDbGrid :=aDbGrid; end; procedure TDS2Excel.IncColRow; begin if FDbGrid <>nil then begin if FCol = FDbGrid.Columns.Count - 1 then begin Inc(FRow); FCol :=0; end else Inc(FCol); end else begin if FCol = FDataSet.FieldCount - 1 then begin Inc(FRow); FCol :=0; end else Inc(FCol); end; end; procedure TDS2Excel.WriteBlankCell; begin CXlsBlank[2] := FRow; CXlsBlank[3] := FCol; Stream.WriteBuffer(CXlsBlank, SizeOf(CXlsBlank)); IncColRow; end; procedure TDS2Excel.WriteFloatCell(const AValue: Double); begin CXlsNumber[2] := FRow; CXlsNumber[3] := FCol; Stream.WriteBuffer(CXlsNumber, SizeOf(CXlsNumber)); Stream.WriteBuffer(AValue, 8); IncColRow; end; procedure TDS2Excel.WriteIntegerCell(const AValue: Integer); var V: Integer; begin CXlsRk[2] := FRow; CXlsRk[3] := FCol; Stream.WriteBuffer(CXlsRk, SizeOf(CXlsRk)); V := (AValue shl 2) or 2; Stream.WriteBuffer(V, 4); IncColRow; end; procedure TDS2Excel.WriteStringCell(const AValue: string); var L: Word; _str : AnsiString; begin _str := AnsiString(AValue); // in delphi XE, there will be error for unicode, fix me !!!!!!!!!!! --by genispan L := Length(_str); CXlsLabel[1] := 8 + L; CXlsLabel[2] := FRow; CXlsLabel[3] := FCol; CXlsLabel[5] := L; Stream.WriteBuffer(CXlsLabel, SizeOf(CXlsLabel)); Stream.WriteBuffer(Pointer(_str)^, L); IncColRow; end; procedure TDS2Excel.WritePrefix; begin Stream.WriteBuffer(CXlsBof, SizeOf(CXlsBof)); Stream.WriteBuffer(cxlscodepage, SizeOf(cxlscodepage)); end; procedure TDS2Excel.WriteSuffix; begin Stream.WriteBuffer(CXlsEof, SizeOf(CXlsEof)); end; procedure TDS2Excel.WriteTitle; var n: word; begin if FDbGrid <> nil then for n := 0 to FDBGrid.Columns.Count - 1 do WriteStringCell(FDBGrid.Columns[n].Title.Caption) else for n := 0 to FDataSet.FieldCount - 1 do WriteStringCell(FDataSet.Fields[n].FieldName); end; procedure TDS2Excel.WriteDataCell; var n: word; begin WritePrefix; if FWillWriteHead then WriteTitle; FDataSet.DisableControls; FBookMark := FDataSet.GetBookmark; FDataSet.First; if FDbGrid=nil then begin while not FDataSet.Eof do begin for n := 0 to FDataSet.FieldCount - 1 do begin try if FDataSet.Fields[n].IsNull then WriteBlankCell else begin case FDataSet.Fields[n].DataType of ftSmallint, ftInteger, ftWord, ftAutoInc, ftBytes: WriteIntegerCell(FDataSet.Fields[n].AsInteger); ftFloat, ftCurrency, ftBCD: WriteFloatCell(FDataSet.Fields[n].AsFloat); ftTypedBinary: else WriteStringCell(FDataSet.Fields[n].AsString); end; end; except WriteBlankCell; end; end; FDataSet.Next; end; end else begin while not FDbGrid.DataSource.DataSet.Eof do begin for n := 0 to FDbGrid.Columns.Count - 1 do begin if FDbGrid.Columns[n].Field.IsNull then WriteBlankCell else begin case FDbGrid.Columns[n].Field.DataType of ftSmallint, ftInteger, ftWord, ftAutoInc, ftBytes: WriteIntegerCell(FDbGrid.Columns[n].Field.AsInteger); ftFloat, ftCurrency, ftBCD: WriteFloatCell(FDbGrid.Columns[n].Field.AsFloat); else WriteStringCell(FDbGrid.Columns[n].Field.AsString); end; end; end; FDbGrid.DataSource.DataSet.Next end; end; WriteSuffix; if FDataSet.BookmarkValid(FBookMark) then FDataSet.GotoBookmark(FBookMark); FDataSet.EnableControls; end; procedure TDS2Excel.Save2Stream(aStream: TStream); begin FCol := 0; FRow := 0; Stream := aStream; WriteDataCell; end; procedure TDS2Excel.Save2File(FileName: string; WillWriteHead: Boolean); var aFileStream: TFileStream; begin FWillWriteHead := WillWriteHead; if FileExists(FileName) then DeleteFile(FileName); aFileStream := TFileStream.Create(FileName, fmCreate); Try Save2Stream(aFileStream); Finally aFileStream.Free; end; end; procedure TDS2Excel.Save2FileS(WillWriteHead: Boolean); var SaveDialog11: TSaveDialog; begin SaveDialog11 := TSaveDialog.Create(nil); Try SaveDialog11.Filter := 'Excel|*.xls'; SaveDialog11.InitialDir := 'C:\'; SaveDialog11.FileName:='*.xls'; if not SaveDialog11.Execute then exit; if FileExists(SaveDialog11.FileName) then DeleteFile(SaveDialog11.FileName); Save2File(SaveDialog11.FileName, WillWriteHead); Finally SaveDialog11.Free; end; end; end.
标签:begin,end,TDS2Excel,Excel,dataset,FDataSet,UNICODE,FDbGrid,procedure 来源: https://www.cnblogs.com/jijm123/p/16189861.html