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    public static string encrypt(string text)
    {
        X509Certificate2 cert = LoadCert(EnumCipheringTarget.ClientServer);
        RSACryptoServiceProvider publicprovider = (RSACryptoServiceProvider)cert.PublicKey.Key;
        byte[] encrypted = publicprovider.Encrypt(GetBytes(text), false);
        return GetString(encrypted);
    }
    public static string decrypt(string text)
    {
        X509Certificate2 cert = LoadCert(EnumCipheringTarget.ClientServer);
        RSACryptoServiceProvider provider = (RSACryptoServiceProvider)cert.PrivateKey;
        byte[] decryptedBytes = provider.Decrypt(GetBytes(text), false);
        return GetString(decryptedBytes);
    }
    private static X509Certificate2 LoadCert(EnumCipheringTarget cipherTarget)
    {
        X509Store store = new X509Store(StoreLocation.CurrentUser);
        store.Open(OpenFlags.ReadOnly);
        X509Certificate2Collection certCollection = store.Certificates;
        X509Certificate2 cert = null;

        string certSubject = "";
        switch (cipherTarget)
        {
            case EnumCipheringTarget.ServerDB:
                certSubject = "CN=MY_DB_CERTIFICATE";
                break;

            default:
                return null;
        }

        foreach (X509Certificate2 c in certCollection)
        {
            if (c.Subject == certSubject)
            {
                cert = c;
                break;
            }
        }
        store.Close();
        return cert;
    }
    static byte[] GetBytes(string str)
    {
        byte[] bytes = new byte[str.Length * sizeof(char)];
        System.Buffer.BlockCopy(str.ToCharArray(), 0, bytes, 0, bytes.Length);
        return bytes;
    }
    static string GetString(byte[] bytes)
    {
        char[] chars = new char[bytes.Length / sizeof(char)];
        System.Buffer.BlockCopy(bytes, 0, chars, 0, bytes.Length);
        return new string(chars);
    }