C#使用DES和AES实现加密解密功能示例

using System;
using System.Text;
using System.Security.Cryptography;
using System.IO;
namespace MyCryptography
{
  /// <summary>
  /// DES加密解密
  /// </summary>
  public class DES
  {
    /// <summary>
    /// 获取密钥
    /// </summary>
    private static string Key
    {
      get { return @"P@+#wG+Z"; }
    }
    /// <summary>
    /// 获取向量
    /// </summary>
    private static string IV
    {
      get { return @"L%n67}GMk@k%:~Y"; }
    }
    /// <summary>
    /// DES加密
    /// </summary>
    /// <param name="plainStr">明文字符串</param>
    /// <returns>密文</returns>
    public static string DESEncrypt(string plainStr)
    {
      byte[] bKey = Encoding.UTF8.GetBytes(Key);
      byte[] bIV = Encoding.UTF8.GetBytes(IV);
      byte[] byteArray = Encoding.UTF8.GetBytes(plainStr);
      string encrypt = null;
      DESCryptoServiceProvider des = new DESCryptoServiceProvider();
      try
      {
        using (MemoryStream mStream = new MemoryStream())
        {
          using (CryptoStream cStream = new CryptoStream(mStream,des.CreateEncryptor(bKey,bIV),CryptoStreamMode.Write))
          {
            cStream.Write(byteArray,byteArray.Length);
            cStream.FlushFinalBlock();
            encrypt = Convert.ToBase64String(mStream.ToArray());
          }
        }
      }
      catch { }
      des.Clear();
      return encrypt;
    }
    /// <summary>
    /// DES解密
    /// </summary>
    /// <param name="encryptStr">密文字符串</param>
    /// <returns>明文</returns>
    public static string DESDecrypt(string encryptStr)
    {
      byte[] bKey = Encoding.UTF8.GetBytes(Key);
      byte[] bIV = Encoding.UTF8.GetBytes(IV);
      byte[] byteArray = Convert.FromBase64String(encryptStr);
      string decrypt = null;
      DESCryptoServiceProvider des = new DESCryptoServiceProvider();
      try
      {
        using (MemoryStream mStream = new MemoryStream())
        {
          using (CryptoStream cStream = new CryptoStream(mStream,des.CreateDecryptor(bKey,byteArray.Length);
            cStream.FlushFinalBlock();
            decrypt = Encoding.UTF8.GetString(mStream.ToArray());
          }
        }
      }
      catch { }
      des.Clear();
      return decrypt;
    }
  }
  /// <summary>
  /// AES加密解密
  /// </summary>
  public class AES
  {
    /// <summary>
    /// 获取密钥
    /// </summary>
    private static string Key
    {
      get { return @")O[NB]6,YF}+efcaj{+oESb9d8>Z'e9M"; }
    }
    /// <summary>
    /// 获取向量
    /// </summary>
    private static string IV
    {
      get { return @"L+~f4,Ir)b$=pkf"; }
    }
    /// <summary>
    /// AES加密
    /// </summary>
    /// <param name="plainStr">明文字符串</param>
    /// <returns>密文</returns>
    public static string AESEncrypt(string plainStr)
    {
      byte[] bKey = Encoding.UTF8.GetBytes(Key);
      byte[] bIV = Encoding.UTF8.GetBytes(IV);
      byte[] byteArray = Encoding.UTF8.GetBytes(plainStr);
      string encrypt = null;
      Rijndael aes = Rijndael.Create();
      try
      {
        using (MemoryStream mStream = new MemoryStream())
        {
          using (CryptoStream cStream = new CryptoStream(mStream,aes.CreateEncryptor(bKey,byteArray.Length);
            cStream.FlushFinalBlock();
            encrypt = Convert.ToBase64String(mStream.ToArray());
          }
        }
      }
      catch { }
      aes.Clear();
      return encrypt;
    }
    /// <summary>
    /// AES加密
    /// </summary>
    /// <param name="plainStr">明文字符串</param>
    /// <param name="returnNull">加密失败时是否返回 null，false 返回 String.Empty</param>
    /// <returns>密文</returns>
    public static string AESEncrypt(string plainStr,bool returnNull)
    {
      string encrypt = AESEncrypt(plainStr);
      return returnNull ? encrypt : (encrypt == null ? String.Empty : encrypt);
    }
    /// <summary>
    /// AES解密
    /// </summary>
    /// <param name="encryptStr">密文字符串</param>
    /// <returns>明文</returns>
    public static string AESDecrypt(string encryptStr)
    {
      byte[] bKey = Encoding.UTF8.GetBytes(Key);
      byte[] bIV = Encoding.UTF8.GetBytes(IV);
      byte[] byteArray = Convert.FromBase64String(encryptStr);
      string decrypt = null;
      Rijndael aes = Rijndael.Create();
      try
      {
        using (MemoryStream mStream = new MemoryStream())
        {
          using (CryptoStream cStream = new CryptoStream(mStream,aes.CreateDecryptor(bKey,byteArray.Length);
            cStream.FlushFinalBlock();
            decrypt = Encoding.UTF8.GetString(mStream.ToArray());
          }
        }
      }
      catch { }
      aes.Clear();
      return decrypt;
    }
    /// <summary>
    /// AES解密
    /// </summary>
    /// <param name="encryptStr">密文字符串</param>
    /// <param name="returnNull">解密失败时是否返回 null，false 返回 String.Empty</param>
    /// <returns>明文</returns>
    public static string AESDecrypt(string encryptStr,bool returnNull)
    {
      string decrypt = AESDecrypt(encryptStr);
      return returnNull ? decrypt : (decrypt == null ? String.Empty : decrypt);
    }
  }
}