数据加密和数据解密有好的理解思路么，提供下，谢谢。

Question

刚接触数据加密和解密知识，不太了解，望各位高手指点一二，以便快速掌握，我在这谢谢了。

Answer 1

http://blog.csdn.net/leehom_zlj/archive/2008/12/21/3575726.aspx
网上很多的呀

Answer 2

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}G\Mk@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, 0, 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, bIV), CryptoStreamMode.Write))
                    {
                        cStream.Write(byteArray, 0, byteArray.Length);
                        cStream.FlushFinalBlock();
                        decrypt = Encoding.UTF8.GetString(mStream.ToArray());
                    }
                }
            }
            catch { }
            des.Clear();            return decrypt;
        }        public static void Main(String []args)
        {
            string sb,sa,sd;
            DES d=new DES();
            Console.WriteLine("请输入需要加密的字符串");
            sb = Console.ReadLine();
            sa = DES.DESEncrypt(sb);
            Console.WriteLine("加密后的字符为"+sa);
            sd = DES.DESDecrypt(sa);
            Console.WriteLine("解密后的字符为"+sd);
        }    }    /// <summary>pu
    /// 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, bIV), CryptoStreamMode.Write))
                    {
                        cStream.Write(byteArray, 0, 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, bIV), CryptoStreamMode.Write))
                    {
                        cStream.Write(byteArray, 0, 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);
        }
    }}

Answer 3

要求不高的话可以用异或、Base64编码

Answer 4

1、.NET 加密解密函数- 松鼠的博客- 博客园
www.cnblogs.com/songsu/articles/992594.html  
2、.NET中加密和解密的实现方法- 开发者在线- www.builder.com.cn
www.builder.com.cn/2007/1104/605875.shtml 
3、C#.Net加密解密(一)
http://blog.sina.com.cn/s/blog_49e36748010006ng.html
4、C#.Net加密解密(二)
http://blog.sina.com.cn/s/blog_49e36748010006nh.html

Answer 5

用DES或者MD5 楼上推荐的blog你也可以看看

Answer 6

sha,md5,des 等加密方法很多
http://msdn.microsoft.com/zh-cn/library/as0w18af(VS.80).aspx