asp.net加密处理

using System;

using System.Security.Cryptography;

using System.Text;

using System.Text.RegularExpressions;

using System.Web;

using System.Web.Security;

 

public sealed class SecurityHelper

    {

        /// <summary>

        /// DES解密。

        /// </summary>

        /// <param name="pToDecrypt">要解密的字符串</param>

        /// <param name="sKey">8位密钥</param>

        /// <returns>已解密的字符串。</returns>

        public static string DESDecrypt(stringpToDecrypt, string sKey)

        {

            DESCryptoServiceProvider des = new DESCryptoServiceProvider();

            //把字符串放入byte数组

            int len = 0;

           len = pToDecrypt.Length / 2 - 1;

            byte[] inputByteArray = newbyte[len + 1];

            int x = 0;

            int i = 0;

            for (x = 0; x <= len; x++)

           {

               i = Convert.ToInt32(pToDecrypt.Substring(x* 2, 2), 16);

               inputByteArray[x] = Convert.ToByte(i);

           }

            //建立加密对象的密钥和偏移量，此值重要，不能修改

           des.Key = ASCIIEncoding.ASCII.GetBytes(sKey);

           des.IV = ASCIIEncoding.ASCII.GetBytes(sKey);

           System.IO.MemoryStream ms = new System.IO.MemoryStream();

            CryptoStream cs = newCryptoStream(ms, des.CreateDecryptor(), CryptoStreamMode.Write);

           cs.Write(inputByteArray, 0, inputByteArray.Length);

           cs.FlushFinalBlock();

            return Encoding.Default.GetString(ms.ToArray());

        }

 

        /// <summary>

        /// DES加密函数

        /// </summary>

        /// <param name="pToEncrypt">要加密的字符串</param>

        /// <param name="sKey">8位密钥</param>

        /// <returns>加密后的字符串</returns>

        public static string DESEncrypt(stringpToEncrypt, string sKey)

        {

            DESCryptoServiceProvider des = new DESCryptoServiceProvider();

            byte[] inputByteArray = null;

           inputByteArray = Encoding.Default.GetBytes(pToEncrypt);

            //建立加密对象的密钥和偏移量

            //原文使用ASCIIEncoding.ASCII方法的GetBytes方法

            //使得输入密码必须输入英文文本

            des.Key = ASCIIEncoding.ASCII.GetBytes(sKey);

           des.IV = ASCIIEncoding.ASCII.GetBytes(sKey);

            //写二进制数组到加密流

            //(把内存流中的内容全部写入)

           System.IO.MemoryStream ms = new System.IO.MemoryStream();

            CryptoStream cs = newCryptoStream(ms, des.CreateEncryptor(), CryptoStreamMode.Write);

            //写二进制数组到加密流

            //(把内存流中的内容全部写入)

           cs.Write(inputByteArray, 0, inputByteArray.Length);

           cs.FlushFinalBlock();

 

            //建立输出字符串     

            StringBuilder ret = newStringBuilder();

            byte b = 0;

            foreach (byteb_loopVariable in ms.ToArray())

           {

               b = b_loopVariable;

               ret.AppendFormat("{0:X2}",b);

            }

            return ret.ToString();

        }

 

        /// <summary>

        /// 处理为合法Windows文件名

        /// </summary>

        /// <param name="strFileName">源文件名字符串</param>

        /// <returns>合法的Windows文件名</returns>

        public static string FileNameFilter(stringstrFileName)

        {

            if (!string.IsNullOrEmpty(strFileName))

           {

               strFileName.Replace("<","");

               strFileName.Replace(">","");

               strFileName.Replace("\\", "");

               strFileName.Replace("/", "");

               strFileName.Replace(":", "");

               strFileName.Replace("*", "");

               strFileName.Replace("?", "");

               strFileName.Replace("|", "");

               strFileName.Replace("\"","");

               return strFileName;

           }

            else

           {

               return "";

           }

        }

 

        /// <summary>

        /// HTML及脚本过滤器

        /// </summary>

        /// <param name="htmlCode">待处理字符串</param>

        /// <returns>处理后的字符串</returns>

        public static string HtmlFilter(stringhtmlCode)

        {

            if (!string.IsNullOrEmpty(htmlCode))

           {

               //过滤脚本

               htmlCode = Regex.Replace(htmlCode, "<script[^>]*?>.*?</script>","", RegexOptions.IgnoreCase);

 

               //过滤HTML

               htmlCode = Regex.Replace(htmlCode, @"<(.[^>]*)>", "", RegexOptions.IgnoreCase);

               htmlCode = Regex.Replace(htmlCode, "([\\r\\n])[\\s]+", "", RegexOptions.IgnoreCase);

               htmlCode = Regex.Replace(htmlCode, "<!--.*?-->", "", RegexOptions.IgnoreCase);

               htmlCode = Regex.Replace(htmlCode, "&(nbsp|#160);", " ", RegexOptions.IgnoreCase);

 

               htmlCode.Replace("<", "");

               htmlCode.Replace(">", "");

               htmlCode.Replace("'", "‘");

               htmlCode.Replace("\\r\\n", "");

               htmlCode.Replace("" + (char)13 + ""+ "" + (char)10+ "", "");

               htmlCode = HttpContext.Current.Server.HtmlEncode(htmlCode).Trim();

               return htmlCode;

           }

            else

           {

               return "";

           }

        }

 

 

        /// <summary>

        /// 产生随机密码

        /// </summary>

        /// <param name="length">密码长度</param>

        /// <returns></returns>

        public static string GetRandomPassword(intlength)

        {

            var chars = "abcdefghijklmnopqrstuvwxyz1234567890ABCDEFGHIJKLMNOPQRSTUVWXYZ!@#$%^&*()".ToCharArray();

            var password = string.Empty;

            var random = new Random();

 

            for (var i = 0; i< length; i++)

           {

               var x = random.Next(1, chars.Length);

               if (!password.Contains(chars.GetValue(x).ToString()))

               {

                   password += chars.GetValue(x);

               }

               else

               {

                   i--;

               }

           }

 

            return password;

        }

    }

此类是关于加密的处理类，转载