PemReader r = new PemReader(new StreamReader("Files/pubkey.pem"));

AsymmetricKeyParameter pubKey = (AsymmetricKeyParameter)r.ReadObject();

PemReader r = new PemReader(new StreamReader("Files/prvkey.pem"));

AsymmetricKeyParameter prvKey = (AsymmetricKeyParameter)r.ReadObject();

FileStream ms = new FileStream("store.p12",OpenMode.Open);

Pkcs12Store store = new Pkcs12StoreBuilder().Build();

store.Load(ms, "".ToCharArray());

//获取第一个别名

IEnumerator itor = store.Aliases.GetEnumerator();

itor.MoveNext();

string alins = itor.Current.ToString();

AsymmetricKeyParameter prvKey=null;

AsymmetricKeyParameter pubKey=null;

if(sotre.IsKeyEntry(alins))

　　prvKey = store.GetKey(alins).Key;

cert = store.GetCertificate(alins).Certificate;

pubkey=cert.GetPublicKey();

AsymmetricKeyParameter prvKey=...;

AsymmetricKeyParameter pubKey=...;

//公钥加密

string origin="abcd1234";

byte[] originbytes=Encoding.Default.getBytes(origin);

IBufferedCipher c = CipherUtilities.GetCipher("RSA/ECB/PKCS1Padding");

c.Init(true, pubKey);

byte[] encryBytes = c.DoFinal(origin);

string encryStr=Encoding.Default.GetString(encryBytes);

//私钥解密

IBufferedCipher c = CipherUtilities.GetCipher("RSA/ECB/PKCS1Padding");

c.Init(false, prvKey);

byte[] recoverBytes=c.DoFinal(encryBytes );

string recover=Encoding.Default.GetString(recoverBytes);