delphi数据库中关于图像存取的知识

Question

uses Jpeg;存图像
proceudre TMainForm.SavePicture(const FileName: string):
begin
  with Table1 do
  begin
    Append;
    FieldByName('Name').AsString := ExtractFileName(FileName);
    TBlobField(FieldByName('Data')).LoadFromFile(FileName);
    Post;
  end;
end;procedure TForm1.ShowPicture;
var
  JpegImage: TJpegImage;
  FileName: string;
begin
  FileName := 'c:\' + Table1.FieldByName('Name').AsString;
  TBlobField(Table1.FieldByName('Data')).SaveToFile(FileName);  
  if LowerCase(ExtractFileExt(FileName)) = '.jpg' then
  begin
    JpegImage := TJpegImage.Create;
    JpegImage.LoadFromFile(FileName);
    Image1.Picture.Graphic.Assign(JpegImage);
    JpegImage.Free;
  end
  else
    Image1.Picture.LoadFromFile(FileName);
end;