C#使用DES加密字符串示例

using System;
using System.IO;
using System.Security.Cryptography;
using System.Text;

namespace Library
{
    public class EncryptHelpr
    {
        private static readonly string key = "1234abcd";
        private static readonly string iv = "12345678";

        /// <summary>
        /// 加密
        /// </summary>
        /// <param name="data"></param>
        /// <returns></returns>
        public static string Encrypt(string data)
        {
            return Encrypt(data, Encoding.UTF8);
        }

        /// <summary>
        /// 加密
        /// </summary>
        /// <param name="data"></param>
        /// <param name="encode"></param>
        /// <returns></returns>
        public static string Encrypt(string data, Encoding encode)
        {
            StringBuilder result = new StringBuilder();
            byte[] dataByteArray = encode.GetBytes(data);
            DESCryptoServiceProvider provider = new DESCryptoServiceProvider();
            provider.Key = Encoding.ASCII.GetBytes(key);
            provider.IV = Encoding.ASCII.GetBytes(iv);
            using (MemoryStream memory = new MemoryStream())
            {
                using (CryptoStream crypto = new CryptoStream(memory, provider.CreateEncryptor(), CryptoStreamMode.Write))
                {
                    crypto.Write(dataByteArray, 0, dataByteArray.Length);
                    crypto.FlushFinalBlock();
                    foreach (byte item in memory.ToArray())
                    {
                        result.AppendFormat("{0:X2}", item);
                    }
                }                
            }
            return result.ToString();
        }

        /// <summary>
        /// 解密
        /// </summary>
        /// <param name="data"></param>
        /// <returns></returns>
        public static string Decrypt(string data)
        {
            return Decrypt(data, Encoding.UTF8);
        }

        /// <summary>
        /// 解密
        /// </summary>
        /// <param name="data"></param>
        /// <param name="encode"></param>
        /// <returns></returns>
        public static string Decrypt(string data, Encoding encode)
        {
            string result = string.Empty;
            byte[] dataByteArray = new byte[data.Length / 2];
            for (int n = 0; n < dataByteArray.Length; n++)
            {
                dataByteArray[n] = (byte)Convert.ToInt32(data.Substring(n * 2, 2), 0x10);
            }
            DESCryptoServiceProvider provider = new DESCryptoServiceProvider();
            provider.Key = Encoding.ASCII.GetBytes(key);
            provider.IV = Encoding.ASCII.GetBytes(iv);
            using (MemoryStream memory = new MemoryStream())
            {
                using (CryptoStream crypto = new CryptoStream(memory, provider.CreateDecryptor(), CryptoStreamMode.Write))
                {
                    crypto.Write(dataByteArray, 0, dataByteArray.Length);
                    crypto.FlushFinalBlock();
                    result = encode.GetString(memory.ToArray());
                }                
            }
            return result;
        }
    }
}

string str = EncryptHelpr.Encrypt("http://www.mzwu.com/");
Console.WriteLine(str);
Console.WriteLine(EncryptHelpr.Decrypt(str));