s2阶段项目

//TvProgram类

public DateTime PlayTime { get; set; }  //播出时间
public string Time { get; set; }  //时段
public string Name { get; set; }   //名称
public string TvPath { get; set; }   //视频路径

//父类ChannelBase--abstract类

public string ChannelName { get; set; }  //频道名称
public string ChannelPath { get; set; }  //频道路径
public List<TvProgram> TvList;  //节目列表
public abstract void Fetch();

//子类TypeA

//北京电视台
public override void Fetch()
{
   if(this.TvList==null)
   {
      TvList = new List<TvProgram>();
   }
      XmlDocument xmlDoc = new XmlDocument();
      xmlDoc.Load(@"files/北京电视台.xml");
      XmlNode xn=xmlDoc.DocumentElement;
       foreach(XmlNode node in xn.ChildNodes )
       {
          if (node.Name == "tvProgramTable")
          {

            foreach(XmlNode xne in node.ChildNodes )
            {
              TvProgram program = new TvProgram();
              program.PlayTime =Convert.ToDateTime( xne["playTime"].InnerText);
              program.Time = xne["meridien"].InnerText;
              program.Name = xne["programName"].InnerText;
              program.TvPath = xne["path"].InnerText;
              TvList.Add(program);
            }
          }
      }
}

//子类TypeB

 //凤凰卫视
        public override void Fetch()
        {
            if (this.TvList == null)
            {
                TvList = new List<TvProgram>();
            }
            XmlDocument xmlDoc = new XmlDocument();
            xmlDoc.Load(ChannelPath);
            XmlNode xn = xmlDoc.DocumentElement;
            foreach(XmlNode node in xn.ChildNodes )
            {
                if (node.Name == "ProgramList")
                {
                    foreach(XmlNode ne in node.ChildNodes )