c# 加密解密示例

using System.Security.Cryptography;

        public class DESEncrypt
        {
            #region ========加密========
            /// <summary>
            /// 加密
            /// </summary>
            /// <param name="Text"></param>
            /// <returns></returns>
            public static string Encrypt(string Text)
            {
                return Encrypt(Text, "SKYWISWARE");
            }
            public static string Encrypt(string Text, string sKey)
            {
                DESCryptoServiceProvider des = new DESCryptoServiceProvider();
                byte[] inputByteArray;
                inputByteArray = Encoding.Default.GetBytes(Text);
                des.Key = ASCIIEncoding.ASCII.GetBytes(sKey.Substring(0, 8));
                des.IV = ASCIIEncoding.ASCII.GetBytes(sKey.Substring(0, 8));
                System.IO.MemoryStream ms = new System.IO.MemoryStream();
                CryptoStream cs = new CryptoStream(ms, des.CreateEncryptor(), CryptoStreamMode.Write);
                cs.Write(inputByteArray, 0, inputByteArray.Length);
                cs.FlushFinalBlock();
                StringBuilder ret = new StringBuilder();
                foreach (byte b in ms.ToArray())
                {
                    ret.AppendFormat("{0:X2}", b);
                }
                return ret.ToString();
            }
            #endregion

            #region ========解密========
            /// <summary>
            /// 解密
            /// </summary>
            /// <param name="Text"></param>
            /// <returns></returns>
            public static string Decrypt(string Text)
            {
                return Decrypt(Text, "SKYWISWARE");
            }
            public static string Decrypt(string Text, string sKey)
            {
                DESCryptoServiceProvider des = new DESCryptoServiceProvider();
                int len;
                len = Text.Length / 2;
                byte[] inputByteArray = new byte[len];
                int x, i;
                for (x = 0; x < len; x++)
                {
                    i = Convert.ToInt32(Text.Substring(x * 2, 2), 16);
                    inputByteArray[x] = (byte)i;
                }
                des.Key = ASCIIEncoding.ASCII.GetBytes(sKey.Substring(0, 8));
                des.IV = ASCIIEncoding.ASCII.GetBytes(sKey.Substring(0, 8));
                System.IO.MemoryStream ms = new System.IO.MemoryStream();
                CryptoStream cs = new CryptoStream(ms, des.CreateDecryptor(), CryptoStreamMode.Write);
                cs.Write(inputByteArray, 0, inputByteArray.Length);
                cs.FlushFinalBlock();
                return Encoding.Default.GetString(ms.ToArray());
            }
            #endregion
        }