通过Google浏览器Cookie文件获取cookie信息，80以上版本有效

 public class ReadCookie
    {
        /// <summary>
        /// </summary>
        /// <param name="hostName"></param>
        /// <returns></returns>
        public static SeleCookie ReadCookies(string hostName,string cookiePath,string domain)
        {
            //测试用
            cookiePath = @"C: \Users\xxx\AppData\Local\Google\Chrome\User Data\Local State";
            domain = "%xxx.com";
            SeleCookie cc = new SeleCookie();
            if (hostName == null) throw new System.ArgumentNullException("hostName");

            var dbPath = System.Environment.GetFolderPath(System.Environment.SpecialFolder.LocalApplicationData) + @"\Google\Chrome\User Data\Default\Cookies";
            if (!System.IO.File.Exists(dbPath)) throw new System.IO.FileNotFoundException("Cant find cookie store", dbPath); // race condition, but i'll risk it

            var connectionString = "Data Source=" + dbPath + ";pooling=false";

            using (var conn = new System.Data.SQLite.SQLiteConnection(connectionString))
            using (var cmd = conn.CreateCommand())
            {
                conn.Close();
                cmd.CommandText = $"select * from cookies  where host_key like '{domain}'";
                #region 查看cookie表
                SQLiteDataAdapter da = new SQLiteDataAdapter(cmd.CommandText, conn);
                DataSet ds = new DataSet();
                da.Fill(ds, "cookiestable");
                #endregion

                var prm = cmd.CreateParameter();
                prm.ParameterName = "hostName";
                prm.Value = hostName;
                cmd.Parameters.Add(prm);

                conn.Open();
                using (var reader = cmd.ExecuteReader())
                {
                    string encKey = File.ReadAllText(cookiePath);
                    encKey = JObject.Parse(encKey)["os_crypt"]["encrypted_key"].ToString();
                    var decodedKey = System.Security.Cryptography.ProtectedData.Unprotect(Convert.FromBase64String(encKey).Skip(5).ToArray(), null, System.Security.Cryptography.DataProtectionScope.LocalMachine);
                    try
                    {
                        var propInfo = typeof(SeleCookie).GetProperties().Where(x => x.IsDefined(typeof(CustomAttribute), false) && x.Name == reader[2].ToString() && !x.Name.Equals("Item"));
                        while (reader.Read())
                        {
                            byte[] encryptedData = (byte[])reader[12];
                            var _cookie = _decryptWithKey(encryptedData, decodedKey, 3);
                            foreach (var prop in propInfo)
                            {
                                prop.SetValue(cc, _cookie ?? string.Empty);
                            }
                        }

                    }
                    finally
                    {
                        conn.Close();
                    }

                }
                if (conn.State != ConnectionState.Closed)
                {
                    conn.Close();
                }
                return cc;
            }

        }
        private static string _decryptWithKey(byte[] message, byte[] key, int nonSecretPayloadLength)
        {
            const int KEY_BIT_SIZE = 256;
            const int MAC_BIT_SIZE = 128;
            const int NONCE_BIT_SIZE = 96;

            if (key == null || key.Length != KEY_BIT_SIZE / 8)
                throw new ArgumentException(String.Format("Key needs to be {0} bit!", KEY_BIT_SIZE), "key");
            if (message == null || message.Length == 0)
                throw new ArgumentException("Message required!", "message");

            using (var cipherStream = new MemoryStream(message))
            using (var cipherReader = new BinaryReader(cipherStream))
            {
                var nonSecretPayload = cipherReader.ReadBytes(nonSecretPayloadLength);
                var nonce = cipherReader.ReadBytes(NONCE_BIT_SIZE / 8);
                var cipher = new GcmBlockCipher(new AesEngine());
                var parameters = new AeadParameters(new KeyParameter(key), MAC_BIT_SIZE, nonce);
                cipher.Init(false, parameters);
                var cipherText = cipherReader.ReadBytes(message.Length);
                var plainText = new byte[cipher.GetOutputSize(cipherText.Length)];
                try
                {
                    var len = cipher.ProcessBytes(cipherText, 0, cipherText.Length, plainText, 0);
                    cipher.DoFinal(plainText, len);
                }
                catch (InvalidCipherTextException)
                {
                    return null;
                }
                return Encoding.Default.GetString(plainText);
            }
        }

    }

需要引用类库：

System.Security.Cryptography.ProtectedData

BouncyCastle

System.Data.SQLite.Core

Newtonsoft.Json