why error?

Question

>> cobi(小新国际)　
当然active了:)

Answer 1

//please try
procedure TForm1.editClick(Sender: TObject);
var
  Stream1, Stream2 : TBlobStream;
begin
  Stream1 := TBlobStream.Create(Table1blob, bmRead);
  try
    Table2.Edit;
    Stream2 := TBlobStream.Create(Table2blob,bmReadWrite);
    try
      //Stream1.Position:=0;
      Stream1.Seek(0,soFromBeginning);
      Stream1.Truncate;
      Stream2.CopyFrom(Stream1, Stream1.Size);
      Table2.Post;
    finally
      Stream2.Free;
    end;
  finally
    Stream1.Free;
  end;
end;

Answer 2

to icehill()　
Stream1.Seek(0,soFromBeginning);
Stream1.Truncate;
Stream2.CopyFrom(Stream1, Stream1.Size);
我觉得没有什么必要试了，Truncate方法把后面的内容全部去掉了,还copyfrom做什么??