using System;

using System.Security.Cryptography;

using System.IO;

using System.Text;

namespace Tools

{

    ///

    /// Security 的摘要说明。

    /// Security类实现.NET框架下的加密和解密。

    /// CopyRight [email]KangSoft@Hotmail.com[/email]@[email]Hotmail.com@hotmail.com[/email]

    ///

    public class Security

    {

        string _QueryStringKey = "abcdefgh"; //URL传输参数加密Key

        string _PassWordKey = "hgfedcba";　//PassWord加密Key

        public Security()

        {

            //

            // TODO: 在此处添加构造函数逻辑

            //

        }

        ///

        /// 加密URL传输的字符串

        ///

        public string EncryptQueryString(string QueryString)

        {

            return Encrypt(QueryString, _QueryStringKey);

        }

        ///

        /// 解密URL传输的字符串

        ///

        public string DecryptQueryString(string QueryString)

        {

            return Decrypt(QueryString, _QueryStringKey);

        }

        ///

        /// 加密帐号口令

        ///

        public string EncryptPassWord(string PassWord)

        {

            return Encrypt(PassWord, _PassWordKey);

        }

        ///

        /// 解密帐号口令

        ///

        public string DecryptPassWord(string PassWord)

        {

            return Decrypt(PassWord, _PassWordKey);

        }

        ///

        /// DEC 加密过程

        ///

        public string Encrypt(string pToEncrypt, string sKey)

        {

            DESCryptoServiceProvider des = new DESCryptoServiceProvider();　//把字符串放到byte数组中

            byte[] inputByteArray = Encoding.Default.GetBytes(pToEncrypt);

            //byte[]　inputByteArray=Encoding.Unicode.GetBytes(pToEncrypt);

            des.Key = ASCIIEncoding.ASCII.GetBytes(sKey);　//建立加密对象的密钥和偏移量

            des.IV = ASCIIEncoding.ASCII.GetBytes(sKey);　 //原文使用ASCIIEncoding.ASCII方法的GetBytes方法

            MemoryStream ms = new MemoryStream();　　 //使得输入密码必须输入英文文本

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

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

            cs.FlushFinalBlock();

            StringBuilder ret = new StringBuilder();

            foreach (byte b in ms.ToArray())

            {

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

            }

            ret.ToString();

            return ret.ToString();

        }

        ///

        /// DEC 解密过程

        ///

        public string Decrypt(string pToDecrypt, string sKey)

        {

            DESCryptoServiceProvider des = new DESCryptoServiceProvider();

            byte[] inputByteArray = new byte[pToDecrypt.Length / ];

            for (int x = ; x < pToDecrypt.Length / ; x++)

            {

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

                inputByteArray[x] = (byte)i;

            }

            des.Key = ASCIIEncoding.ASCII.GetBytes(sKey);　//建立加密对象的密钥和偏移量，此值重要，不能修改

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

            MemoryStream ms = new MemoryStream();

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

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

            cs.FlushFinalBlock();

            StringBuilder ret = new StringBuilder();　//建立StringBuild对象，CreateDecrypt使用的是流对象，必须把解密后的文本变成流对象

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

        }

        ///

        /// 检查己加密的字符串是否与原文相同

        ///

        public bool ValidateString(string EnString, string FoString, int Mode)

        {

            switch (Mode)

            {

                default:

                case :

                    if (Decrypt(EnString, _QueryStringKey) == FoString.ToString())

                    {

                        return true;

                    }

                    else

                    {

                        return false;

                    }

                case :

                    if (Decrypt(EnString, _PassWordKey) == FoString.ToString())

                    {

                        return true;

                    }

                    else

                    {

                        return false;

                    }

            }

        }

    }

}