说一说ASP.NET web.config 加密及解密方法 （代码）

/// <summary>
   /// 保护web.config的加密和解密
   /// </summary>
   public class ProtectHelper
   {
       /// <summary>
       /// 解密
       /// </summary>
       /// <param name="pToDecrypt">加密连接字符串</param>
       /// <param name="sKey">自定义密钥</param>
       /// <returns>解密字符串</returns>
       public static string UnProtectSection(string pToDecrypt, string sKey)
       {
           byte[] inputByteArray = Convert.FromBase64String(pToDecrypt);
           using (DESCryptoServiceProvider des = new DESCryptoServiceProvider())
           {
               des.Key = ASCIIEncoding.ASCII.GetBytes(sKey);
               des.IV = ASCIIEncoding.ASCII.GetBytes(sKey);
               System.IO.MemoryStream ms = new System.IO.MemoryStream();
               using (CryptoStream cs = new CryptoStream(ms, des.CreateDecryptor(), CryptoStreamMode.Write))
               {
                   cs.Write(inputByteArray, 0, inputByteArray.Length);
                   cs.FlushFinalBlock();
                   cs.Close();
               }
               string str = Encoding.UTF8.GetString(ms.ToArray());
               ms.Close();
               return str;
           }
       }

       /// <summary>
       /// 加密
       /// </summary>
       /// <param name="pToEncrypt">连接字符串</param>
       /// <param name="sKey">自定义密钥</param>
       /// <returns>加密字符串</returns>
       public static string ProtectSection(string pToEncrypt, string sKey)
       {
           using (DESCryptoServiceProvider des = new DESCryptoServiceProvider())
           {
               byte[] inputByteArray = Encoding.UTF8.GetBytes(pToEncrypt);
               des.Key = ASCIIEncoding.ASCII.GetBytes(sKey);
               des.IV = ASCIIEncoding.ASCII.GetBytes(sKey);
               System.IO.MemoryStream ms = new System.IO.MemoryStream();
               using (CryptoStream cs = new CryptoStream(ms, des.CreateEncryptor(), CryptoStreamMode.Write))
               {
                   cs.Write(inputByteArray, 0, inputByteArray.Length);
                   cs.FlushFinalBlock();
                   cs.Close();
               }
               string str = Convert.ToBase64String(ms.ToArray());
               ms.Close();
               return str;
           }
       }
   }