请问如何将一幅JPG图片保存到BLOB字段中?

Question

我想一幅JPG图片保存到BLOB字段中,但不知道我的代码错在哪里?JPG图片根本就没有保存进BLOB字段里!运行到下面这句时提示 "Jpeg error #50",保存的图片仍然是一片空白. tblobfield(table1.FieldByName('photo')).LoadFromStream(tmp);
procedure TForm1.Button2Click(Sender: TObject);
var
  tmp: tmemorystream;
  tmpjpg: tjpegimage;
begin
  tmp:=TmemoryStream.Create;
  tmpjpg:=tjpegimage.create;
  tmpjpg.LoadFromfile(openpicturedialog1.filename);
  tmpjpg.savetostream(tmp);
  tmp.seek(0,0);
  table1.Edit;
  tblobfield(table1.FieldByName('photo')).LoadFromStream(tmp);//这里出错
  tmpjpg.free;
  tmp.Free;
end;

Answer 1

procedure TForm1.Button2Click(Sender: TObject);
var
  tmp: tmemorystream;
  tmpjpg: tjpegimage;
begin
  tmp:=TmemoryStream.Create;
  tmpjpg:=tjpegimage.create;
  tmpjpg.LoadFromfile(openpicturedialog1.filename);
  tmpjpg.savetostream(tmp);
  //tmp.seek(0,0);不需要
  table1.Edit;
  tblobfield(table1.FieldByName('photo')).LoadFromStream(tmp);//这里出错
  tmpjpg.free;
  tmp.Free;
end;

Answer 2

procedure TForm1.Button2Click(Sender: TObject);
var
  tmp: tmemorystream;
begin
  tmp:=TmemoryStream.Create;
  tmp.loadfromfile(openpicturedialog1.filename);
  table1.Edit;
  tblobfield(table1.FieldByName('photo')).LoadFromStream(tmp);//这里出错
  tmp.Free;
end;

Answer 3

连上数据库，用cxDBImage设置相应字段即可。

Answer 4

cxDBImage.Picture.LoadFromFile(openpicturedialog1.filename)