[C#] 常用工具类——加密解密类

using System;

using System.Configuration;

using System.Collections.Generic;

using System.Text;

using System.Web;

using System.Web.UI;

using System.Web.UI.HtmlControls;

using System.Web.UI.WebControls;

using System.Web.UI.WebControls.WebParts;

using System.Web.Security;

using System.Drawing;

using System.Drawing.Imaging;

using System.Drawing.Drawing2D;

using System.IO;

using System.Security.Cryptography;

 

namespace Utils

{

    /// <summary>

    /// <para>　</para>

    /// 　常用工具类——加密解密类

    /// <para>　-------------------------------------------------</para>

    /// <para>　StringEncode：返回 HTML 字符串的编码结果</para>

    /// <para>　StringDecode：返回 HTML 字符串的解码结果</para>

    /// <para>　UrlEncode：返回 URL 字符串的编码结果</para>

    /// <para>　UrlDecode：返回 URL 字符串的解码结果</para>

    /// <para>　DESEncrypt：DES加密</para>

    /// <para>　DESDecrypt：DES解密</para>

    /// <para>　MD5：MD5函数</para>

    /// <para>　SHA256：SHA256函数</para>

    /// </summary>

    public class EncyptHelper

    {

        /// <summary>

        /// 32位Key值：

        /// </summary>

        public static byte[] DESKey = new byte[] { 0x03, 0x0B, 0x13, 0x1B, 0x23, 0x2B, 0x33, 0x3B, 0x43, 0x4B, 0x9B, 0x93, 0x8B, 0x83, 0x7B, 0x73, 0x6B, 0x63, 0x5B, 0x53, 0xF3, 0xFB, 0xA3, 0xAB, 0xB3, 0xBB, 0xC3, 0xEB, 0xE3, 0xDB, 0xD3, 0xCB };

 

        #region 返回 HTML 字符串的编码结果

        /// <summary>

        /// 返回 HTML 字符串的编码结果

        /// </summary>

        /// <param name="str">字符串</param>

        /// <returns>编码结果</returns>

        public static string StringEncode(string str)

        {

            return HttpUtility.HtmlEncode(str);

        }

        #endregion

 

        #region 返回 HTML 字符串的解码结果

        /// <summary>

        /// 返回 HTML 字符串的解码结果

        /// </summary>

        /// <param name="str">字符串</param>

        /// <returns>解码结果</returns>

        public static string StringDecode(string str)

        {

            return HttpUtility.HtmlDecode(str);

        }

        #endregion

 

        #region 返回 URL 字符串的编码结果

        /// <summary>

        /// 返回 URL 字符串的编码结果

        /// </summary>

        /// <param name="str">字符串</param>

        /// <returns>编码结果</returns>

        public static string UrlEncode(string str)

        {

            return HttpUtility.UrlEncode(str);

        }

        #endregion

 

        #region 返回 URL 字符串的解码结果

        /// <summary>

        /// 返回 URL 字符串的解码结果

        /// </summary>

        /// <param name="str">字符串</param>

        /// <returns>解码结果</returns>

        public static string UrlDecode(string str)

        {

            return HttpUtility.UrlDecode(str);

        }

        #endregion

 

        #region DES加密

        /// <summary>

        /// DES加密

        /// </summary>

        /// <param name="strSource">待加密字串</param>

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

        public static string DESEncrypt(string strSource)

        {

            return DESEncrypt(strSource, DESKey);

        }

        /// <summary>

        /// DES加密

        /// </summary>

        /// <param name="strSource">待加密字串</param>

        /// <param name="key">Key值</param>

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

        public static string DESEncrypt(string strSource, byte[] key)

        {

            SymmetricAlgorithm sa = Rijndael.Create();

            sa.Key = key;

            sa.Mode = CipherMode.ECB;

            sa.Padding = PaddingMode.Zeros;

            MemoryStream ms = new MemoryStream();

            CryptoStream cs = new CryptoStream(ms, sa.CreateEncryptor(), CryptoStreamMode.Write);

            byte[] byt = Encoding.Unicode.GetBytes(strSource);

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

            cs.FlushFinalBlock();

            cs.Close();

            return Convert.ToBase64String(ms.ToArray());

        }

        #endregion

 

        #region DES解密

        /// <summary>

        /// DES解密

        /// </summary>

        /// <param name="strSource">待解密的字串</param>

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

        public static string DESDecrypt(string strSource)

        {

            return DESDecrypt(strSource, DESKey);

        }

        /// <summary>

        /// DES解密

        /// </summary>

        /// <param name="strSource">待解密的字串</param>

        /// <param name="key">32位Key值</param>

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

        public static string DESDecrypt(string strSource, byte[] key)

        {

            SymmetricAlgorithm sa = Rijndael.Create();

            sa.Key = key;

            sa.Mode = CipherMode.ECB;

            sa.Padding = PaddingMode.Zeros;

            ICryptoTransform ct = sa.CreateDecryptor();

            byte[] byt = Convert.FromBase64String(strSource);

            MemoryStream ms = new MemoryStream(byt);

            CryptoStream cs = new CryptoStream(ms, ct, CryptoStreamMode.Read);

            StreamReader sr = new StreamReader(cs, Encoding.Unicode);

            return sr.ReadToEnd();

        }

        #endregion        

 

        #region MD5函数

        /// <summary>

        /// MD5函数,需引用：using System.Security.Cryptography;

        /// </summary>

        /// <param name="str">原始字符串</param>

        /// <returns>MD5结果</returns>

        public static string MD5(string str)

        {

            byte[] b = Encoding.Default.GetBytes(str);

            b = new MD5CryptoServiceProvider().ComputeHash(b);

            string ret = "";

            for (int i = 0; i < b.Length; i++)

                ret += b[i].ToString("x").PadLeft(2, '0');

            return ret;

        }

        #endregion

 

        #region SHA256函数

        /// <summary>

        /// SHA256函数

        /// </summary>

        /// /// <param name="str">原始字符串</param>

        /// <returns>SHA256结果</returns>

        public static string SHA256(string str)

        {

            byte[] SHA256Data = Encoding.UTF8.GetBytes(str);

            SHA256Managed Sha256 = new SHA256Managed();

            byte[] Result = Sha256.ComputeHash(SHA256Data);

            return Convert.ToBase64String(Result);  //返回长度为44字节的字符串

        }

        #endregion

    }

}