Indy10中的DecodeToStream

Question

I want to upgrade my application from Indy 9 to 10 with Delphi 2007. Now this don't compile anymore as DecodeToStream is not found. The code use Bold framwork as there is reference to BoldElement.

Any alternative methods to call ?

UPDATE (I think I simplify previous example too much)

Original code:

    BlobStreamStr  : String;
    MIMEDecoder    : TidDecoderMIME; 

    if (BoldElement is TBATypedBlob) then
    begin
      BlobStreamStr := copy(ChangeValue,pos(']',ChangeValue)+1,maxint);
      (BoldElement as TBATypedBlob).ContentType := copy(ChangeValue,2,pos(']',ChangeValue)-2);

      MIMEDecoder := TidDecoderMIME.Create(nil);
      try
        MIMEDecoder.DecodeToStream(BlobStreamStr,(BoldElement as TBATypedBlob).CreateBlobStream(bmWrite));
      finally
        FreeAndNil(MIMEDecoder);
      end;
    end

After my change:

    BlobStreamStr  : String;
    MIMEDecoder    : TidDecoderMIME; 
    LStream        : TIdMemoryStream;

    if (BoldElement is TBATypedBlob) then
    begin
      BlobStreamStr := copy(ChangeValue, pos(']', ChangeValue) + 1, maxint);
      (BoldElement as TBATypedBlob).ContentType := copy(ChangeValue, 2, pos(']',ChangeValue)-2);

      MIMEDecoder := TidDecoderMIME.Create(nil);
      LStream := TIdMemoryStream.Create;
      try
        MIMEDecoder.DecodeBegin(LStream);
        MIMEDecoder.Decode(BlobStreamStr, 0, Length(BlobStreamStr));
        LStream.Position := 0;
        ReadTIdBytesFromStream(LStream, DecodedBytes, Length(BlobStreamStr));

        // Should memory for this stream be released ??
        (BoldElement as TBATypedBlob).CreateBlobStream(bmWrite).Write(DecodedBytes[0], Length(DecodedBytes));
      finally
        MIMEDecoder.DecodeEnd;
        FreeAndNil(LStream);
        FreeAndNil(MIMEDecoder);
      end;
    end

But I'm not confident at all of my changes as I don't know Indy so much. So all comments are welcome. One thing I don't understand is the call to CreateBlobStream. I should check with FastMM so it isn't a memleak.

Answer 1

Yes they changed a lot between 9 and 10.

Now you have "DecodeBytes" instead of DecodeToStream I think. So something like this should do it:

var
  DecodedBytes: TIdBytes;
begin
  MIMEDecoder := TidDecoderMIME.Create(nil);
  try
    DecodedBytes := MIMEDecoder.DecodeBytes(vString);
    vStream.Write(DecodedBytes[0], Length(DecodedBytes));
  finally
    FreeAndNil(MIMEDecoder);
  end;
end;

Answer 2

Using TIdDecoder.DecodeBegin() is the correct way to decode to a TStream. However, you do not need the intermediate TIdMemoryStream (which, BTW, has not existed in Indy 10 for a long time now - consider upgrading to a newer release). You can pass the Blob stream directly instead, for example:

var
  BlobElement    : TBATypedBlob;
  BlobStreamStr  : String; 
  BlobStream     : TStream;
  MIMEDecoder    : TidDecoderMIME;  
begin 
  ...
  if BoldElement is TBATypedBlob then 
  begin 
    BlobElement := BoldElement as TBATypedBlob;

    BlobStreamStr := Copy(ChangeValue, Pos(']',ChangeValue)+1, Maxint); 
    BlobElement.ContentType := Copy(ChangeValue, 2, Pos(']',ChangeValue)-2); 

    BlobStream := BlobElement.CreateBlobStream(bmWrite);
    try
      MIMEDecoder := TidDecoderMIME.Create(nil); 
      try 
        MIMEDecoder.DecodeBegin(BlobStream);
        try
          MIMEDecoder.Decode(BlobStreamStr); 
        finally
          MIMEDecoder.DecodeEnd;
        end;
      finally 
        FreeAndNil(MIMEDecoder); 
      end; 
    finally
      FreeAndNil(BlobStream);
    end;
  end;
  ...
end;