delphi - 如何清除jpeg图像？

Question

如何清除TJPEGImage图像？

JPG.Width := 0 技巧不起作用。另外，我不想创建一个空位图(0x0 像素)并将其分配给 jpeg。

Answer 1

您可能会使用类似的内容(此处使用插入的类来访问 protected 方法):

type
  TJPEGImage = class(jpeg.TJPEGImage);

implementation

procedure TForm1.Button1Click(Sender: TObject);
var
  JPEGImage: TJPEGImage;
begin
  JPEGImage := TJPEGImage.Create;
  try
    // this should recreate the internal bitmap
    JPEGImage.NewBitmap;
    // this should recreate the internal image stream
    JPEGImage.NewImage;
    // here the memory used by the image should be released
  finally
    JPEGImage.Free;
  end;
end;