文件加密

using System.IO;
using System.Runtime.Serialization.Formatters.Binary;
using System.Security.Cryptography;
using System.IO.Compression;
using System;
public class Serialize
{
    // 用于初始化对称密钥
    private static byte[] key =
    {
        1, 2, 3, 4, 5, 6, 7, 8, 9, 0, 1, 2, 3, 4, 5, 6,
            7, 8, 9, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 0, 1, 2
        };

    //始化向量IV
    private static byte[] IV = { 1, 2, 3, 4, 5, 6, 7, 8, 9, 0, 1, 2, 3, 4, 5, 6 };

    /// <summary>
    /// 将对象压缩加密到字节数据
    /// </summary>
    /// <param name="obj">要压缩加密的对象</param>
    /// <returns>处理后生成的字节数组</returns>
    public static byte[] CompressEncryptToBytes(object obj)
    {
        // 建立对称密码信息
        MemoryStream ms = new MemoryStream();

        //此处也可以创建其他的解密类实例，但注意不同(长度)的加密类要求不同的密钥Key和初始化向量IV
        RijndaelManaged RM = new RijndaelManaged();

        // CryptoStream 加密转换流
        CryptoStream EnCrpStrm = new CryptoStream(ms, RM.CreateEncryptor(key, IV), CryptoStreamMode.Write);
        DeflateStream zip = new DeflateStream(EnCrpStrm, CompressionMode.Compress, true);
        try
        {
            BinaryFormatter serializer = new BinaryFormatter();
            serializer.Serialize(zip, obj);
            zip.Close();        // 在返回（return）这前一定要进行关闭
            EnCrpStrm.FlushFinalBlock();    // 在返回（return）这前一定要进行调用。
            return ms.ToArray();
        }
        catch (Exception e)
        {
            Console.WriteLine(e.ToString());
            return null;
        }
        finally
        {
            EnCrpStrm.Close();
            ms.Close();
        }
    }

    /// <summary>
    /// 将字节数组进行解密解压还原成对象
    /// </summary>
    /// <param name="ary">要处理的字节数组</param>
    /// <returns>被还原的对象</returns>
    public static object DecompressDecryptToObject(byte[] ary)
    {
        MemoryStream ms = new MemoryStream(ary);
        RijndaelManaged RM = new RijndaelManaged();
        CryptoStream DeCrpStrm = new CryptoStream(ms, RM.CreateDecryptor(key, IV), CryptoStreamMode.Read);
        DeflateStream UnZip = new DeflateStream(DeCrpStrm, CompressionMode.Decompress);
        try
        {
            BinaryFormatter serializer = new BinaryFormatter();
            return serializer.Deserialize(UnZip);
        }
        catch (System.Exception e)
        {
            Console.WriteLine(e.ToString());
            return null;
        }
        finally
        {
            UnZip.Close();
            DeCrpStrm.Close();
            ms.Close();
        }
    }

    /// <summary>
    /// 将对象压缩到字节数组
    /// </summary>
    /// <param name="obj">要压缩的对象</param>
    /// <returns>压缩后的字节数组</returns>
    public static byte[] CompressedToBytes(object obj)
    {
        MemoryStream ms = new MemoryStream();
        DeflateStream zip = new DeflateStream(ms, CompressionMode.Compress, true);
        try
        {
            BinaryFormatter serializer = new BinaryFormatter();
            serializer.Serialize(zip, obj);
            zip.Close();
            byte[] ary = ms.ToArray();
            ms.Close();
            return ary;
        }
        catch (Exception e)
        {
            zip.Close();
            ms.Close();
            Console.WriteLine(e.ToString());
            return null;
        }
    }

    /// <summary>
    /// 解压缩后对象
    /// </summary>
    /// <param name="ary">字节数组</param>
    /// <returns>对象</returns>
    public static object DecompressToObject(byte[] ary)
    {
        MemoryStream ms = new MemoryStream(ary);
        DeflateStream UnZip = new DeflateStream(ms, CompressionMode.Decompress);
        try
        {
            BinaryFormatter serializer = new BinaryFormatter();
            object obj = serializer.Deserialize(UnZip);
            UnZip.Close();
            ms.Close();
            return obj;
        }
        catch (Exception e)
        {
            UnZip.Close();
            ms.Close();
            Console.WriteLine(e.ToString());
            return null;
        }
    }
}