void Main()
{
	/*
		increments an alpha?-numeric token by 1
	*/
	var maxToken = "INV-001";

	maxToken.Dump();
	var newToken = IncrementToken(maxToken);
	newToken.Dump();
}


public string IncrementToken(string token)
{
	var re = new Regex(@"(.+)(\d+)$");
	var result = re.Match(token);
	var prefix = result.Groups[1].Value;
	var digits = result.Groups[2].Value;
	int num;
	int.TryParse(token.Replace(prefix,""), out num);
	var newCode = prefix + (++num).ToString().PadLeft(digits.Length, '0');
	return newCode;
}