手动生成xml

private void Button1_Click(object sender, System.EventArgs e)
  {
   //创建新的xml
   XmlDocument doc = new XmlDocument();
   doc.LoadXml("<company></company>"); 
   //设置版本信息
   XmlDeclaration xmldecl;
   xmldecl = doc.CreateXmlDeclaration("1.0",null,null);
   xmldecl.Encoding="gb2312";
   //xmldecl.Standalone="yes";   

   //
   XmlElement root = doc.DocumentElement;
   doc.InsertBefore(xmldecl, root);  
   //设置根结点
   XmlElement newCompany = doc.DocumentElement;
   //创建新的name
   XmlElement newName = doc.CreateElement("name");
   newName.InnerText = "公司名称"; //公司名称
   //加入父结点
   newCompany.AppendChild(newName);
           
   XmlElement newInfo = doc.CreateElement("info");
   newInfo.InnerText = "简介"; //简介
   newCompany.AppendChild(newInfo);

   XmlElement newContactinfo = doc.CreateElement("contactinfo");
   newContactinfo.InnerText = "网址"; //网址
   newCompany.AppendChild(newContactinfo);

   XmlElement newContactperson = doc.CreateElement("contactperson");
   newContactperson.InnerText = "姓名"; //姓名
   newCompany.AppendChild(newContactperson);

   XmlElement newContactzip = doc.CreateElement("contactzip");
   newContactzip.InnerText = "邮编"; //邮编
   newCompany.AppendChild( newContactzip );

   XmlElement newContactadd = doc.CreateElement("contactadd");
   newContactadd.InnerText = "地址"; //地址
   newCompany.AppendChild( newContactadd );

   //工作列表
   //先创建jobs类表

   XmlElement newJobs = doc.CreateElement("jobs");
   newCompany.AppendChild( newJobs );

   //DataSet ds = new DataSet();
   //if(ds!=null)
   //{
   //foreach(DataRow dr in ds.Tables[0].Rows)
   for(int i=0;i<5;i++)
   {
    XmlElement newJob = doc.CreateElement("job");
    newJobs.AppendChild( newJob );

    XmlElement newTitle = doc.CreateElement("title");
    newTitle.InnerText = i.ToString(); //职位名称
    newJob.AppendChild( newTitle );

    XmlElement newUrl = doc.CreateElement("url");
    newUrl.InnerText = "http://www.020job.com"; //网址
    newJob.AppendChild( newUrl );
   }
   //}

   //doc.DocumentElement.AppendChild(newCompany);

   XmlTextWriter tr = new XmlTextWriter(Server.MapPath(Random_str()),System.Text.Encoding.GetEncoding("gb2312"));
   doc.WriteContentTo(tr);
   tr.Close();
  }

  private string Random_str()
  {
   Random oRan = new System.Random();
   string fileName =
    DateTime.Now.Year.ToString() +
    DateTime.Now.Month.ToString() +
    DateTime.Now.Day.ToString() +
    DateTime.Now.Hour.ToString() +
    DateTime.Now.Minute.ToString() +
    DateTime.Now.Second.ToString() +
    oRan.Next(9999).ToString() +
    ".xml";

   return fileName ;
  }