public string Encode(string value, out int length)
{
if (string.IsNullOrEmpty(value))
{
length = 0;
return(string.Empty);
}
var bytes = ASCIIEncoding.ASCII.GetBytes(value.ToCharArray(), 0, Math.Min(value.Length, MaxLength));
var bits = new BitBag();
for (int b = 0; b < bytes.Length; bits.Pack(bytes[b++]))
{
}
var outbytes = bits.ToOctets();
var result = new StringBuilder();
for (int b = 0; b < outbytes.Length; result.Append(outbytes[b++].ToString("X2")))
{
}
length = bytes.Length;
return(result.ToString());
}
public string Decode(string value)
{
if (string.IsNullOrWhiteSpace(value) || value.Trim().Length < 2 || value.Trim().Length % 2 > 0 || !Regex.IsMatch(value, @"^[a-fA-F0-9]+$"))
{
return(string.Empty);
}
var source = value.Trim();
var packed = new byte[source.Length >> 1];
for (int p = 0; p < source.Length - 1; packed[p >> 1] = byte.Parse(source.Substring(p, 2), NumberStyles.HexNumber), p += 2)
{
}
var bits = new BitBag(packed);
var unpacked = bits.Unpack();
return(ASCIIEncoding.ASCII.GetString(unpacked));
}