Delphi – Upgrade Indy9 to Indy10

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;

you have a method with same name

procedure TIdUDPClient.SendBuffer(const AHost: string; const APort: TIdPort;
  const ABuffer: TIdBytes);

Instead of an untyped buffer it expects an array of bytes. What is your data like? You just need to write your data as an array of bytes. Something like:

var
 Buffer: TIdBytes;
begin
 SetLength(Buffer, YourSizeOfData);
 Move(YourData, Buffer[0], YourSizeOfData);
 FIdUDPClient.SendBuffer('255.255.255.255', UIPerfPort, Buffer);
end;

But as I said it depends on the type of the data. The approach is ok however.

EDIT:

Now that I can see that you have a record you have two options:

Just move the whole record to array of bytes.

Move(@aRecord, Buffer[0], (6 + TimeClassMax) * SizeOf(Integer));

Have a CopyToBytes method in your record that does the actual copy. More general I guess.

TTimeDataRecord = record
  Size: Integer; //Size of record structure is transfered and compared for safty reasons.
  ClientCount: Integer;
  AccumulatedTime: Integer; //This is the accumulated time busy in microseconds
  CurrentMessageTime: Integer; //This is the time the current message has been  processed. If several computers report a high value at the same time it indicates a freeze!
  TotalTimeFrame: Integer; //This is the total time measured in microseconds
  MessageCount: Integer;
  TimeClasses: array [0..TimeClassMax] of Integer;
  procedure CopyToBytes(var Buffer: TIdBytes);
end

Implementation of the CopyToBytes

procedure TTimeDataRecord.CopyToBytes(var Buffer: TIdBytes);
begin
  // copy the data however you see fit
end;