复制代码 代码如下:

public class MD5
{
        static List<KeyValuePair<char, char>> MappingList;
        #region 加密      public static string Encrypt(string str)
        /// <summary>
        /// 加密
        /// </summary>
        /// <param name=\"str\">要加密的字符串</param>
        /// <returns>返回结果的字符串</returns>
        public static string Encrypt(string str)
        {
            MappingList = new List<KeyValuePair<char, char>>();
            for (char c = \'0\'; c <= \'9\'; c++)
                MappingList.Add(new KeyValuePair<char, char>(c, (char)(c - \'0\' + \'a\')));
            for (char c = \'a\'; c <= \'f\'; c++)
                MappingList.Add(new KeyValuePair<char, char>(c, (char)(c - \'a\' + \'u\')));
            return Encoding.ASCII.GetBytes(str)
                .Select((b, i) => (b ^ ((byte)(0xa0 + i))).ToString(\"x2\"))
                .Aggregate(\"\", (s, c) => s + c)
                .ToCharArray().Select(c => MappingList.First(kv => kv.Key == c).Value)
                .Aggregate(\"\", (s, c) => s + c);
        }
        #endregion
        #region 解密       public static string Decrypt(string str)
        /// <summary>
        /// 解密
        /// </summary>
        /// <param name=\"str\">解密的字符串</param>
        /// <returns>返回结果字符串</returns>
        public static string Decrypt(string str)
        {
            string base16 = str.ToCharArray()
                .Select(c => MappingList.First(kv => kv.Value == c).Key)
                .Aggregate(\"\", (s, c) => s + c);
            return Encoding.ASCII.GetString((new byte[base16.Length / 2])
                .Select((b, i) => (byte)(Convert.ToByte(base16.Substring(i * 2, 2), 16) ^ ((byte)(0xa0 + i)))).ToArray());
        }
        #endregion
}