C# 字符串 分割 反转 Base64

string pwd = "";
            //字符串 ToBase64
            byte[] bytes = Encoding.Default.GetBytes(pwd);
            pwd = Convert.ToBase64String(bytes);
            //字符串分割反转。
            var strs = pwd.ToCharArray().Reverse<char>();
            pwd = string.Join("",strs ); //合并字符串

            strs = pwd.ToCharArray().Reverse<char>();
            pwd = string.Join("", strs);
            //字符串 FromBase64

            byte[] outputb = Convert.FromBase64String(pwd);
            pwd = Encoding.Default.GetString(outputb);