Title: How to print a TImage
1.}
uses
Printers;
procedure TForm1.Button1Click(Sender: TObject);
var
ScaleX, ScaleY: Integer;
RR: TRect;
begin
with Printer do
begin
BeginDoc;
// Mit BeginDoc wird ein Druckauftrag initiiert.
// The StartDoc function starts a print job.
try
ScaleX := GetDeviceCaps(Handle, logPixelsX) div PixelsPerInch;
ScaleY := GetDeviceCaps(Handle, logPixelsY) div PixelsPerInch;
// Informationen ¨¹ber die Aufl?sung
// Retrieves information about the Pixels per Inch of the Printer.
RR := Rect(0, 0, Image1.picture.Width * scaleX, Image1.Picture.Height * ScaleY);
Canvas.StretchDraw(RR, Image1.Picture.Graphic);
// An die Aufl?sung anpassen
// Stretch to fit
finally
EndDoc; //Methode EndDoc beendet den aktuellen Druckauftrag und schlie?t die
// Textdatei-Variable.
// Steht in finally - um auch bei Abbruch des Druckauftrages Papierausgabe
// sicherzustellen
end;
end;
end;
{2.}
{************************************************************************}
// Based on posting to borland.public.delphi.winapi by Rodney E Geraghty, 8/8/97.
procedure PrintBitmap(Canvas: TCanvas; DestRect: TRect; Bitmap: TBitmap);
var
BitmapHeader: pBitmapInfo;
BitmapImage: Pointer;
HeaderSize: DWORD;
ImageSize: DWORD;
begin
GetDIBSizes(Bitmap.Handle, HeaderSize, ImageSize);
GetMem(BitmapHeader, HeaderSize);
GetMem(BitmapImage, ImageSize);
try
GetDIB(Bitmap.Handle, Bitmap.Palette, BitmapHeader^, BitmapImage^);
StretchDIBits(Canvas.Handle,
DestRect.Left, DestRect.Top, // Destination Origin
DestRect.Right - DestRect.Left, // Destination Width
DestRect.Bottom - DestRect.Top, // Destination Height
0, 0, // Source Origin
Bitmap.Width, Bitmap.Height, // Source Width & Height
BitmapImage,
TBitmapInfo(BitmapHeader^),
DIB_RGB_COLORS,
SRCCOPY)
finally
FreeMem(BitmapHeader);
FreeMem(BitmapImage)
end
end {PrintBitmap};
{3.}
{************************************************************************}
// from www.experts-exchange.com
uses
printers;
procedure DrawImage(Canvas: TCanvas; DestRect: TRect; ABitmap: TBitmap);
var
Header, Bits: Pointer;
HeaderSize: DWORD;
BitsSize: DWORD;
begin
GetDIBSizes(ABitmap.Handle, HeaderSize, BitsSize);
Header := AllocMem(HeaderSize);
Bits := AllocMem(BitsSize);
try
GetDIB(ABitmap.Handle, ABitmap.Palette, Header^, Bits^);
StretchDIBits(Canvas.Handle, DestRect.Left, DestRect.Top,
DestRect.Right, DestRect.Bottom,
0, 0, ABitmap.Width, ABitmap.Height, Bits, TBitmapInfo(Header^),
DIB_RGB_COLORS, SRCCOPY);
finally
FreeMem(Header, HeaderSize);
FreeMem(Bits, BitsSize);
end;
end;
procedure PrintImage(Image: TImage; ZoomPercent: Integer);
// if ZoomPercent=100, Image will be printed across the whole page
var
relHeight, relWidth: integer;
begin
Screen.Cursor := crHourglass;
Printer.BeginDoc;
with Image.Picture.Bitmap do
begin
if ((Width / Height) (Printer.PageWidth / Printer.PageHeight)) then
begin
// Stretch Bitmap to width of PrinterPage
relWidth := Printer.PageWidth;
relHeight := MulDiv(Height, Printer.PageWidth, Width);
end
else
begin
// Stretch Bitmap to height of PrinterPage
relWidth := MulDiv(Width, Printer.PageHeight, Height);
relHeight := Printer.PageHeight;
end;
relWidth := Round(relWidth * ZoomPercent / 100);
relHeight := Round(relHeight * ZoomPercent / 100);
DrawImage(Printer.Canvas, Rect(0, 0, relWidth, relHeight), Image.Picture.Bitmap);
end;
Printer.EndDoc;
Screen.cursor := crDefault;
end;
// Example Call:
procedure TForm1.Button1Click(Sender: TObject);
begin
// Print image at 40% zoom:
PrintImage(Image1, 40);
end;