这样写会出错!这怎么读JPG呢?

[sgw520]

这样写会出错!这怎么读JPG呢?
var
F:tmemorystream;
begin
F:=tmemorystream.Create ;
f.LoadFromFile('c:\b.jpg');//换成BMP的文件是可以的.
f.Position :=0;
image1.Picture.Bitmap.LoadFromStream(f);
f.Free ;
end;
这样写会出错!是因为b.jpg不是BMP,所以不行.这怎么通过流的方式读JPG呢?

[window_8888]

image1.Picture.Bitmap.LoadFromStream(f);
这句话有问题.
是bitmap.load是bmp流形式.
你存成文件,再loadfromfile吧

[gzmhero]

google搜索一下不就好了么？

// 用到 jpeg 单元
procedure TForm1.BitBtn1Click(Sender: TObject);
var picstream:Tblobstream;
pic:Tjpegimage;
jpegStream:TMemoryStream;
begin

table1.Active:=true;
jpegStream:=TMemoryStream.Create;
(table1.fieldbyname('picture') as TBlobField).SaveToStream(JpegStream);
JpegStream.Position:=0;
try
image1.Picture.Graphic:=nil;
image1.Picture.Graphic:=TJpegImage.Create;
image1.Picture.Graphic.LoadFromStream(JpegStream); //读Jpeg
except
Image1.Picture.Bitmap.LoadFromStream(JpegStream); //读Bmp
end;
jpegStream.Free;

(table1.FieldByName('picture') as tblobfield).SaveToFile('d:\aaaaa.jpg');

end;

[7年]

uses加jpeg.

[huayufei]