GDI+可以动态加载吗？
我用的是这个 http://www.mitov.com/html/igdi_.html
我想实现这样的效果：如果系统中有GDI+库，则使用GDI+；没有GDI+库，则不使用GDI+，并且不会引起异常。
可以把它转化成这个形式吗：
unit RT_tags;
interface
uses
Windows;
var
TAGS_Read: function (handle: DWORD; const fmt: PAnsiChar): PAnsiChar; stdcall;
TAGS_GetLastErrorDesc: function : PAnsiChar; stdcall;
TAGS_GetVersion: function : DWORD; stdcall;
var BassTag_Handle : Thandle = 0;
function Load_BassTagDLL(const dllfilename : string) : boolean;
procedure Unload_BassTagDLL;
implementation
function Load_BassTagDLL(const dllfilename : string) : boolean;
var
oldmode : integer;
begin
if BassTag_Handle <> 0 then // is it already there ?
result := true
else begin {go & load the dll}
oldmode := SetErrorMode($8001);
BassTag_Handle := LoadLibrary(pchar(dllfilename)); // obtain the handle we want
SetErrorMode(oldmode);
if BassTag_Handle <> 0 then
begin {now we tie the functions to the VARs from above}
@TAGS_Read := GetProcAddress(BassTag_Handle, 'TAGS_Read');
@TAGS_GetLastErrorDesc := GetProcAddress(BassTag_Handle, 'TAGS_GetLastErrorDesc');
@TAGS_GetVersion := GetProcAddress(BassTag_Handle, 'TAGS_GetVersion');
// check if everything is linked in correctly
if (@TAGS_Read = nil){ or
(@TAGS_GetLastErrorDesc = nil) or
(@TAGS_GetVersion = nil)} then
begin
FreeLibrary(BassTag_Handle);
BassTag_Handle := 0;
end;
end;
result := (BassTag_Handle <> 0);
end;
end;
procedure Unload_BassTagDLL;
begin
if BassTag_Handle <> 0 then
FreeLibrary(BassTag_Handle);
BassTag_Handle := 0;
end;
end.
SuppressBackgroundThread: True;
SuppressExternalCodecs: False);
function LoadGdiPlusMethod(const ProcName: string): Pointer;
begin
Result := nil;
if FGDIPresent then
Result := GetProcAddress(FGDIPlusLibrary, PChar(ProcName));
FGDIPresent := Result <> nil;
end;
begin
if FGDIPresent then
Exit;
FGDIPlusLibrary := SafeLoadLibrary(GDIPlusLibraryName);
FGDIPresent := FGDIPlusLibrary <> 0;
if FGDIPresent then
begin
// GDI+ Memory managment methods loading
GdipAlloc := LoadGdiPlusMethod('GdipAlloc');
GdipFree := LoadGdiPlusMethod('GdipFree');
// GDI+ initialization/finalization methods loading
GdiplusStartup := LoadGdiPlusMethod('GdiplusStartup');
GdiplusShutdown := LoadGdiPlusMethod('GdiplusShutdown');
// GDI+ Brush methods loading
GdipCloneBrush := LoadGdiPlusMethod('GdipCloneBrush');
GdipDeleteBrush := LoadGdiPlusMethod('GdipDeleteBrush');
GdipGetBrushType := LoadGdiPlusMethod('GdipGetBrushType');
// GDI+ Solid Brush methods loading
GdipCreateSolidFill := LoadGdiPlusMethod('GdipCreateSolidFill');
GdipSetSolidFillColor := LoadGdiPlusMethod('GdipSetSolidFillColor');
GdipGetSolidFillColor := LoadGdiPlusMethod('GdipGetSolidFillColor');
// GDI+ Gradient Brush methods loading
GdipCreateLineBrushFromRectI := LoadGdiPlusMethod('GdipCreateLineBrushFromRectI');
GdipGetLineRectI := LoadGdiPlusMethod('GdipGetLineRectI');
GdipSetLineColors := LoadGdiPlusMethod('GdipSetLineColors');
GdipGetLineColors := LoadGdiPlusMethod('GdipGetLineColors');
GdipSetLineWrapMode := LoadGdiPlusMethod('GdipSetLineWrapMode');
GdipGetLineWrapMode := LoadGdiPlusMethod('GdipGetLineWrapMode');
// GDI+ Hatch Brush methods loading
GdipCreateHatchBrush := LoadGdiPlusMethod('GdipCreateHatchBrush');
GdipGetHatchStyle := LoadGdiPlusMethod('GdipGetHatchStyle');
GdipGetHatchForegroundColor := LoadGdiPlusMethod('GdipGetHatchForegroundColor');
GdipGetHatchBackgroundColor := LoadGdiPlusMethod('GdipGetHatchBackgroundColor');
// GDI+ Pen methods loading
GdipCreatePen1 := LoadGdiPlusMethod('GdipCreatePen1');
GdipCreatePen2 := LoadGdiPlusMethod('GdipCreatePen2');
GdipClonePen := LoadGdiPlusMethod('GdipClonePen');
GdipDeletePen := LoadGdiPlusMethod('GdipDeletePen');
GdipGetPenFillType := LoadGdiPlusMethod('GdipGetPenFillType');
GdipSetPenBrushFill := LoadGdiPlusMethod('GdipSetPenBrushFill');
GdipGetPenBrushFill := LoadGdiPlusMethod('GdipGetPenBrushFill');
GdipSetPenColor := LoadGdiPlusMethod('GdipSetPenColor');
GdipGetPenColor := LoadGdiPlusMethod('GdipGetPenColor');
GdipSetPenMode := LoadGdiPlusMethod('GdipSetPenMode');
GdipGetPenMode := LoadGdiPlusMethod('GdipGetPenMode');
GdipSetPenWidth := LoadGdiPlusMethod('GdipSetPenWidth');
GdipGetPenWidth := LoadGdiPlusMethod('GdipGetPenWidth');
GdipGetPenDashStyle := LoadGdiPlusMethod('GdipGetPenDashStyle');
GdipSetPenDashStyle := LoadGdiPlusMethod('GdipSetPenDashStyle');
// GDI+ Graphis methods loading
GdipCreateFromHDC := LoadGdiPlusMethod('GdipCreateFromHDC');
GdipDeleteGraphics := LoadGdiPlusMethod('GdipDeleteGraphics');
GdipGetDC := LoadGdiPlusMethod('GdipGetDC');
GdipReleaseDC := LoadGdiPlusMethod('GdipReleaseDC');
GdipGraphicsClear := LoadGdiPlusMethod('GdipGraphicsClear');
GdipDrawLineI := LoadGdiPlusMethod('GdipDrawLineI');
GdipDrawLinesI := LoadGdiPlusMethod('GdipDrawLinesI');
GdipFillRectangleI := LoadGdiPlusMethod('GdipFillRectangleI');
GdipDrawArcI := LoadGdiPlusMethod('GdipDrawArcI');
GdipDrawBezierI := LoadGdiPlusMethod('GdipDrawBezierI');
GdipDrawRectangleI := LoadGdiPlusMethod('GdipDrawRectangleI');
GdipDrawEllipseI := LoadGdiPlusMethod('GdipDrawEllipseI');
GdipDrawPieI := LoadGdiPlusMethod('GdipDrawPieI');
GdipDrawPolygonI := LoadGdiPlusMethod('GdipDrawPolygonI');
GdipDrawCurve2I := LoadGdiPlusMethod('GdipDrawCurve2I');
GdipDrawClosedCurve2I := LoadGdiPlusMethod('GdipDrawClosedCurve2I');
GdipFillPolygonI := LoadGdiPlusMethod('GdipFillPolygonI');
GdipFillEllipseI := LoadGdiPlusMethod('GdipFillEllipseI');
GdipFillPieI := LoadGdiPlusMethod('GdipFillPieI');
GdipFillClosedCurveI := LoadGdiPlusMethod('GdipFillClosedCurveI');
// added from MSN
GdipLoadImageFromStream := LoadGdiPlusMethod('GdipLoadImageFromStream');
GdipCreateBitmapFromFile := LoadGdiPlusMethod('GdipCreateBitmapFromFile');
GdipCreateBitmapFromStream := LoadGdiPlusMethod('GdipCreateBitmapFromStream');
GdipCreateBitmapFromStreamICM := LoadGdiPlusMethod('GdipCreateBitmapFromStreamICM');
GdipCreateHBITMAPFromBitmap := LoadGdiPlusMethod('GdipCreateHBITMAPFromBitmap');
GdipLoadImageFromFile := LoadGdiPlusMethod('GdipLoadImageFromFile');
GdipGetImageDimension := LoadGdiPlusMethod('GdipGetImageDimension');
GdipDrawImageRectI := LoadGdiPlusMethod('GdipDrawImageRectI');
GdipDisposeImage := LoadGdiPlusMethod('GdipDisposeImage');
GdipGetImageEncodersSize := LoadGdiPlusMethod('GdipGetImageEncodersSize');
GdipGetImageEncoders := LoadGdiPlusMethod('GdipGetImageEncoders');
GdipSaveImageToStream := LoadGdiPlusMethod('GdipSaveImageToStream');
GdipCreateBitmapFromHBITMAP := LoadGdiPlusMethod('GdipCreateBitmapFromHBITMAP');
GdipIsVisibleRect := LoadGdiPlusMethod('GdipIsVisibleRect');
GdipIsVisibleRectI := LoadGdiPlusMethod('GdipIsVisibleRectI');
GdipGetEncoderParameterListSize := LoadGdiPlusMethod('GdipGetEncoderParameterListSize');
GdipGetEncoderParameterList := LoadGdiPlusMethod('GdipGetEncoderParameterList');
GdipCreateBitmapFromGdiDib := LoadGdiPlusMethod('GdipCreateBitmapFromGdiDib');
GdipCreateBitmapFromScan0 := LoadGdiPlusMethod('GdipCreateBitmapFromScan0');
GdipBitmapLockBits := LoadGdiPlusMethod('GdipBitmapLockBits');
GdipBitmapUnlockBits := LoadGdiPlusMethod('GdipBitmapUnlockBits');
GdipDrawImageRectRectI := LoadGdiPlusMethod('GdipDrawImageRectRectI');
GdipDrawImageRectRect := LoadGdiPlusMethod('GdipDrawImageRectRect');
GdipDrawImagePointRect := LoadGdiPlusMethod('GdipDrawImagePointRect');
GdipCloneImage := LoadGdiPlusMethod('GdipCloneImage');
GdipCreateTexture2I := LoadGdiPlusMethod('GdipCreateTexture2I');
GdipCreateImageAttributes := LoadGdiPlusMethod('GdipCreateImageAttributes');
GdipDisposeImageAttributes := LoadGdiPlusMethod('GdipDisposeImageAttributes');
GdipSetImageAttributesColorMatrix := LoadGdiPlusMethod('GdipSetImageAttributesColorMatrix');
GdipAddPathArc := LoadGdiPlusMethod('GdipAddPathArc');
GdipAddPathLine := LoadGdiPlusMethod('GdipAddPathLine');
GdipClosePathFigure := LoadGdiPlusMethod('GdipClosePathFigure');
GdipCreatePath := LoadGdiPlusMethod('GdipCreatePath');
GdipDeletePath := LoadGdiPlusMethod('GdipDeletePath');
GdipDrawPath := LoadGdiPlusMethod('GdipDrawPath');
GdipFillPath := LoadGdiPlusMethod('GdipFillPath');
GdipStartPathFigure := LoadGdiPlusMethod('GdipStartPathFigure');
//lcm
GdipSetInterpolationMode := LoadGdiPlusMethod('GdipSetInterpolationMode');
GdipGetInterpolationMode := LoadGdiPlusMethod('GdipGetInterpolationMode');
GdipCreateCachedBitmap := LoadGdiPlusMethod('GdipCreateCachedBitmap');
GdipDeleteCachedBitmap := LoadGdiPlusMethod('GdipDeleteCachedBitmap');
GdipDrawCachedBitmap := LoadGdiPlusMethod('GdipDrawCachedBitmap');
GdipCreateBitmapFromGraphics := LoadGdiPlusMethod('GdipCreateBitmapFromGraphics');
GdipGetImageGraphicsContext := LoadGdiPlusMethod('GdipGetImageGraphicsContext');
GdipGetImageWidth := LoadGdiPlusMethod('GdipGetImageWidth');
GdipGetImageHeight := LoadGdiPlusMethod('GdipGetImageHeight');
GdipSetCompositingMode := LoadGdiPlusMethod('GdipSetCompositingMode');
GdipGetCompositingMode := LoadGdiPlusMethod('GdipGetCompositingMode');
GdipSetCompositingQuality := LoadGdiPlusMethod('GdipSetCompositingQuality');
GdipGetCompositingQuality := LoadGdiPlusMethod('GdipGetCompositingQuality');
GdipSetSmoothingMode := LoadGdiPlusMethod('GdipSetSmoothingMode');
GdipGetSmoothingMode := LoadGdiPlusMethod('GdipGetSmoothingMode');
GdipCloneBitmapAreaI := LoadGdiPlusMethod('GdipCloneBitmapAreaI');
//
if (GdiPlusStartup(FGDIPlusToken, DefaultStartup, @FGdiPlusHook) <> OK) or
(FGdiPlusHook.NotificationHook(FGDIPlusToken) <> Ok) then
begin
FGDIPresent := False;
FillChar(FGdiPlusHook, SizeOf(FGdiPlusHook), 0);
end;
end;
end;
[解决办法]
没有注意到，不是操作系统自带的吗？
好像xp自带就有。
别的系统，底层类库可能不支持了。
