[Styles]

PHP Code:

        private string GetFriendID(string authid)
        {
            authid.Replace("STEAM_", "");
            string[] split = authid.Split(':');
            return "765611979" + ((Convert.ToInt64(split[2]) * 2) + 60265728 + Convert.ToInt64(split[1])).ToString();
        } 


C# Version