Base64加密/解密

/// <summary>
        /// Base64加密
        /// </summary>
        /// <param name="data"></param>
        /// <returns></returns>
        public static string Base64Encrypt(string data)
        {
            byte[] b = System.Text.Encoding.Default.GetBytes(data);
            return Convert.ToBase64String(b);
        }
        /// <summary>
        /// Base64解密
        /// </summary>
        /// <param name="data"></param>
        /// <returns></returns>
        public static string Base64Decrypt(string data)
        {
            byte[] c = Convert.FromBase64String(data);
            return System.Text.Encoding.Default.GetString(c);
        }