C# RSA

using System;
using System.Security.Cryptography;
using System.Text;

class RSACSPSample
{

static void Main()
    {
       
try
       
{
           
string str_Plain_Text = "How are you?How are you?How are you?How
are you?=-popopolA";
           
Console.WriteLine("明文：" + str_Plain_Text);
           
Console.WriteLine("长度：" +
str_Plain_Text.Length.ToString());
           
Console.WriteLine();

RSACryptoServiceProvider RSA = new
RSACryptoServiceProvider();

string str_Public_Key;
           
string str_Private_Key;
           
string str_Cypher_Text = RSA_Encrypt(str_Plain_Text, out
str_Public_Key,out str_Private_Key);
           
Console.WriteLine("密文：" + str_Cypher_Text);
           
Console.WriteLine("公钥：" + str_Public_Key);
           
Console.WriteLine("私钥：" + str_Private_Key);

string str_Plain_Text2 = RSA_Decrypt(str_Cypher_Text,
str_Private_Key);
           
Console.WriteLine("解密：" + str_Plain_Text2);

Console.WriteLine();
       
}
       
catch (ArgumentNullException)
       
{
           
Console.WriteLine("Encryption failed.");
       
}
    }

//RSA加密,随机生成公私钥对并作为出参返回
    static
public string RSA_Encrypt(string str_Plain_Text, out string
str_Public_Key, out string str_Private_Key)
    {
       
str_Public_Key = "";
       
str_Private_Key = "";
       
UnicodeEncoding ByteConverter = new UnicodeEncoding();
       
byte[] DataToEncrypt =
ByteConverter.GetBytes(str_Plain_Text);
       
try
       
{
           
RSACryptoServiceProvider RSA = new
RSACryptoServiceProvider();
           
str_Public_Key =
Convert.ToBase64String(RSA.ExportCspBlob(false));
           
str_Private_Key =
Convert.ToBase64String(RSA.ExportCspBlob(true));

//OAEP padding is only available on Microsoft Windows XP or
later. 
           
byte[] bytes_Cypher_Text = RSA.Encrypt(DataToEncrypt, false);
           
str_Public_Key =
Convert.ToBase64String(RSA.ExportCspBlob(false));
           
str_Private_Key =
Convert.ToBase64String(RSA.ExportCspBlob(true));
           
string str_Cypher_Text =
Convert.ToBase64String(bytes_Cypher_Text);
           
return str_Cypher_Text;
       
}
       
catch (CryptographicException e)
       
{
           
Console.WriteLine(e.Message);
           
return null;
       
}
    }

//RSA解密
    static
public string RSA_Decrypt(string str_Cypher_Text, string
str_Private_Key)
    {
       
byte[] DataToDecrypt =
Convert.FromBase64String(str_Cypher_Text);
       
try
       
{
           
RSACryptoServiceProvider RSA = new
RSACryptoServiceProvider();
           
//RSA.ImportParameters(RSAKeyInfo);
           
byte[] bytes_Public_Key =
Convert.FromBase64String(str_Private_Key);
           
RSA.ImportCspBlob(bytes_Public_Key);

//OAEP padding is only available on Microsoft Windows XP or
later. 
           
byte[] bytes_Plain_Text = RSA.Decrypt(DataToDecrypt, false);
           
UnicodeEncoding ByteConverter = new UnicodeEncoding();
           
string str_Plain_Text =
ByteConverter.GetString(bytes_Plain_Text);
           
return str_Plain_Text;
       
}
       
catch (CryptographicException e)
       
{
           
Console.WriteLine(e.ToString());
           
return null;
       
}
    }
}