image 数据库传递之间 出错

Question

var 
stream:tmemorystream; if datab.remote_query.Fields[i].DataType=ftblob then 
  begin 
    stream:=tmemorystream.Create; 
    (datab.remote_query.Fields[i] as tblobfield).SaveToStream(stream); 
    tblobfield(datab.local_query.Fields[i]).LoadFromstream(Stream); 
  end;  
显示bitmap image is not valid.应该怎么改呢? 

Answer 1

    FS:=TFileStream.Create(FileName, fmOpenRead);
    TBlobField(ADOQPicture.FieldByName('Picture')).LoadFromStream(FS);    MS:=TMemoryStream.create;
    TBlobField(ADOQPicture.FieldByName('Picture')).SaveToStream(MS) ;    Bmp.LoadFromStream(MS) ;

Answer 2

可能是图形格式不兼容的问题,数据库图片格式什么格式bmp还是jpg,gif...

Answer 3

如果我想将jpeg转成BMP因该怎么写?

Answer 4

var 
stream:tmemorystream; if datab.remote_query.Fields[i].DataType=ftblob then 
  begin 
    stream:=tmemorystream.Create; 
    tblobfield(datab.remote_query.Fields[i]).SaveToStream(stream); 
    stream.Position:=0;
    tblobfield(datab.local_query.Fields[i]).LoadFromstream(Stream); 
    stream.Free;
  end; 

Answer 5

http://www.aiyit.com/software/articleshow.asp?id=571procedure Jpg2Bmp(const source,dest:string);
var
  MyJpeg: TJpegImage;
  bmp: Tbitmap;
begin
bmp:=tbitmap.Create;
MyJpeg:= TJpegImage.Create;
try
  myjpeg.LoadFromFile(source);
  bmp.Assign(myjpeg);
  bmp.SaveToFile(dest);
finally
  bmp.free;
  myjpeg.Free;
end;
end;

Answer 6

procedure CopyBmpToJpeg(BmpFile,JpegFile:string);
var
Bmp:TBitmap;
Jpeg:TJPEGImage;
begin
Bmp:=TBitmap.create;
Jpeg:= TJpegImage.Create;
try
Bmp.LoadFromFile(BmpFile);
Jpeg.Assign(Bmp);
Jpeg.SaveToFile(JpegFile);
finally
Bmp.Free;
Jpeg.Free;
end;
end;