Akka.IO.ByteString.ByteStrings.this C# (CSharp) Method

            public override byte this[int idx]
            {
                get
                {
                    if (0 <= idx && idx < Count)
                    {
                        var pos = 0;
                        var seen = 0;
                        while (idx >= seen + _byteStrings[pos].Count)
                        {
                            seen += _byteStrings[pos].Count;
                            pos += 1;
                        }
                        return _byteStrings[pos][idx - seen];
                    }
                    throw new IndexOutOfRangeException();
                }
            }