public override bool Fallback(byte[] bytesUnknown, int index)
{
// We expect no previous fallback in our buffer
Debug.Assert(iCount < 1, "[DecoderReplacementFallbackBuffer.Fallback] Calling fallback without a previously empty buffer");
cBestFit = TryBestFit(bytesUnknown);
if (cBestFit == '\0')
cBestFit = _oFallback.cReplacement;
iCount = iSize = 1;
return true;
}