Render a TRichEdit text onto a canvas (Views: 29)
Problem/Question/Abstract: How to render a TRichEdit text onto a canvas? Answer: procedure RichEditToCanvas(RichEdit: TRichEdit; Canvas: TCanvas; PixelsPerInch: Integer); var ImageCanvas: TCanvas; fmt: TFormatRange; begin ImageCanvas := Canvas; with fmt do begin hdc := ImageCanvas.Handle; hdcTarget := hdc; // rect needs to be specified in twips (1/1440 inch) as unit rc := Rect(0, 0, ImageCanvas.ClipRect.Right * 1440 div PixelsPerInch, ImageCanvas.ClipRect.Bottom * 1440 div PixelsPerInch ); rcPage := rc; chrg.cpMin := 0; chrg.cpMax := RichEdit.GetTextLen; end; SetBkMode(ImageCanvas.Handle, TRANSPARENT); RichEdit.Perform(EM_FORMATRANGE, 1, Integer(@fmt)); // next call frees some cached data RichEdit.Perform(EM_FORMATRANGE, 0, 0); end; procedure TForm1.Button1Click(Sender: TObject); begin RichEditToCanvas(RichEdit1, Image1.Canvas, Self.PixelsPerInch); Image1.Refresh; end; |