I want to generate RSA key pair in C#. I am able to get xml

Question

I want to generate RSA key pair in C#. I am able to get XML strings of keys, but I need base64 representations of them. Here is my code for XML

RSACryptoServiceProvider rsa = new RSACryptoServiceProvider();
privateKeyXmlText = rsa.ToXmlString(true);
publicKeyXmlText = rsa.ToXmlString(false);

but what I want is something like

privateKeyStr=="MIICITAjBgoqhkiG9w0BDAEDMBUEEKaTCK5mE2MsQANxDAfaJe8CAQoEggH47qb6bFO+a2Fj...";
publicKeyStr == "MIIBKjCB4wYHKoZIzj0CATCB1wIBATAsBgcqhkjOPQEBAiEA/////wAA...";

any ideas?