var provider = new System.Security.Cryptography.RSACryptoServiceProvider(); provider.ImportParameters(your_rsa_key);
var encryptedBytes = provider.Encrypt( System.Text.Encoding.UTF8.GetBytes("Hello World!"), true);
string decryptedTest = System.Text.Encoding.UTF8.GetString(provider.Decrypt(encryptedBytes, true));
For more info, visit MSDN - RSACryptoServiceProvider
On MSDN[
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