streamwriter chopping off the telnet packets

[Naveenv2002]

I am using granados parser for connecting to the telnet and get the data from it. However, every thing appears to be going smooth. But for some reason when I try to write to a string or streamwriter, it looses the final packet. Strangely, If I output the datapackets from the telnet server, it perfectly gets all the packets.

the code snippet is below:

StreamWriter sw = new StreamWriter("c:\\output.txt", true);

public void OnData(byte[] data, int offset, int length)
{
    System.Console.Write(Encoding.UTF8.GetString(data, offset, length));
    outputdata = (Encoding.ASCII.GetString(data, offset, length));
    sw.Write(outputdata);
    //sw.Close();
}

in the above,

System.Console.Write(Encoding.UTF8.GetString(data, offset, length));

outputs the data correctly, however,
in the outputdata string the last packets gets chopped off.

Can someone help what's happening behind. Or is it something I am missing while writing to a file.

[Plater]

One of them uses ascii, one uses utf8.