帮我把这个加密方法转为用asp - .NET技术 / C#

原有C#类如下：只写Encode的两个方法就行了，O(∩_∩)O谢谢~
using System.Security.Cryptography;
using System.IO;
using System.Text;
using System;
/// <summary>
///MDProperty 的摘要说明
/// </summary>
public class MDProperty
{
  // <summary>
  /// 加密
  /// </summary>
  /// <param name="str"></param>
  /// <param name="key"></param>
  /// <returns></returns>
  public static string Encode(string str, string key)
  {
  DESCryptoServiceProvider provider = new DESCryptoServiceProvider();
  provider.Key = Encoding.ASCII.GetBytes(key.Substring(0, 8));
  provider.IV = Encoding.ASCII.GetBytes(key.Substring(0, 8));
  byte[] bytes = Encoding.GetEncoding("GB2312").GetBytes(str);
  MemoryStream stream = new MemoryStream();
  CryptoStream stream2 = new CryptoStream(stream, provider.CreateEncryptor(), CryptoStreamMode.Write);
  stream2.Write(bytes, 0, bytes.Length);
  stream2.FlushFinalBlock();
  StringBuilder builder = new StringBuilder();
  foreach (byte num in stream.ToArray())
  {
  builder.AppendFormat("{0:X2}", num);
  }<