C# 加密

一、RSA加密解密

using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Security.Cryptography;
using System.Text;
using System.Threading.Tasks;

namespace RSADemoTest
{
    class Program
    {
        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();
                Console.ReadKey();
            }
            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));
                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();
                byte[] bytes_Public_Key = Convert.FromBase64String(str_Private_Key);
                RSA.ImportCspBlob(bytes_Public_Key);
                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;
            }
        }
    }
}