[firebase-br] blob / doc

[marcelo]

não estou conseguindo recuperar um arquivo salvo em um blob,
dá um erro:        invalid class typecast

qual tipo de blob devo usar para armazenar doc, xls e outros?


var blob: TBlobStream;
begin
  //blob := q.CreateBlobStream(q.fieldByName('BLOB1') as tblobfield,
bmRead);
  //Blob := TBlobStream.Create(q.Fieldbyname('blob1') as TBlobField,
bmRead);
  //Blob:= TBlobStream.Create(q.Fieldbyname('blob1'), bmReadWrite);
  //Blob:= TBlobStream.Create(q.FieldByName('blob1') as tblobfield,
bmReadWrite);
  //Blob:= TBlobStream.Create(q2blob1, bmReadWrite);
  Blob := TBlobStream.Create(q2.Fieldbyname('blob1') as TBlobField,
bmReadwrite);
  try
    blob.Seek(0, soFromBeginning);
    with TFileStream.Create('c:\temp\'+q2.fieldbyname('nome_arq').asstring,
fmCreate) do
      try
        CopyFrom(blob, blob.Size)
      finally
        Free
      end;
  finally
    blob.Free
  end;