读取XML

 StreamReader sr = new StreamReader(Server.MapPath(datafile));
        XmlDataDocument datadoc = new XmlDataDocument();
        datadoc.DataSet.ReadXml(sr);
        GridView1.DataSource = datadoc.DataSet.Tables[0].DefaultView;
        GridView1.DataBind();
        datadoc = null;
        sr.Close();