System.Text.EncoderFallbackBuffer.Fallback C# (CSharp) Method

        public abstract bool Fallback(char charUnknownHigh, char charUnknownLow, int index);

		public void HandleFallback(ref EncoderFallbackBuffer buffer,
			char[] chars, ref int charIndex, ref int charCount,
			byte[] bytes, ref int byteIndex, ref int byteCount, object state)
		{
			if (buffer == null)
				buffer = EncoderFallback.CreateFallbackBuffer();

			// THIS IS WERE THE BUG IS!! (pruiz)
			if (charCount > 1 && (Char.IsSurrogate(chars[charIndex]) && Char.IsSurrogate(chars[charIndex + 1])))
			{
				buffer.Fallback (chars[charIndex], chars[charIndex + 1], charIndex);
				charIndex++;
				charCount--;
			}
			else
				buffer.Fallback (chars[charIndex], charIndex);

			char[] tmp = new char[buffer.Remaining];
			int idx = 0;
			while (buffer.Remaining > 0)
				tmp[idx++] = buffer.GetNextChar();

			var len = state == null ?
				GetBytes(tmp, 0, tmp.Length, bytes, byteIndex)
				: GetBytesInternal(tmp, 0, tmp.Length, bytes, byteIndex, true, state);
			byteIndex += len;
			byteCount -= len;
		}