.NET使用OpenSSL生成的pem密钥文件【做电子商务的朋友可能需要】(2)

        /// <summary>
        /// 将pem格式私钥转换为RSAParameters
        /// </summary>
        /// <param name="pemFileConent">pem私钥内容</param>
        /// <returns>转换得到的RSAParamenters</returns>
        public static RSAParameters ConvertFromPemPrivateKey(string pemFileConent)
        {
            if (string.IsNullOrEmpty(pemFileConent))
            {
                throw new ArgumentNullException("pemFileConent", "This arg cann't be empty.");
            }
            pemFileConent = pemFileConent.Replace("-----BEGIN RSA PRIVATE KEY-----", "").Replace("-----END RSA PRIVATE KEY-----", "").Replace("\n", "").Replace("\r","");
            byte[] keyData = Convert.FromBase64String(pemFileConent);
            if (keyData.Length < 609)
            {
                throw new ArgumentException("pem file content is incorrect.");
            }

            int index = 11;
            byte[] pemModulus = new byte[128];
            Array.Copy(keyData, index, pemModulus, 0, 128);

            index += 128;
            index += 2;//141
            byte[] pemPublicExponent = new byte[3];
            Array.Copy(keyData, index, pemPublicExponent, 0, 3);

            index += 3;
            index += 4;//148