string转换成xml

    [WebMethod]
    public XmlDocument GESInfo()
    {
        XmlDocument xmldoc = new XmlDocument();
        string info = "<?xml version='1.0' encoding='GB2312'?><GESInfo><City id='苏州' name='苏州' code='1001'><Area id='市区' name='市区' code='10011001' LocationSetup='0'><Place id='观前' name='观前' code='100110011001' LocationSetup='1'><Monitor id='摄像头1' name='摄像头1' code='11000000000000000011200034800000' gesid='abcde1' channelid='1'  VideoScan='1'  Capture='1'  ManualREC='1'  RecPlay ='1' MonControl='1' />    <Monitor id='摄像头2' name='摄像头2' code='11000000000000000011200034800000' gesid='abcde2' channelid='1'  VideoScan='1'  Capture='1'  ManualREC='1'  RecPlay ='1' MonControl='1' /></Place><Place id='石路' name='石路' code='100110011002' LocationSetup='2'><Monitor id='摄像头3' name='摄像头3' code='11000000000000000011200034800000' gesid='abcde3' channelid='1'  VideoScan='1'  Capture='1'  ManualREC='1'  RecPlay ='1' MonControl='1' />    <Monitor id='摄像头4' name='摄像头4' code='11000000000000000011200034800000' gesid='abcde4' channelid='1'  VideoScan='1'  Capture='1'  ManualREC='1'  RecPlay ='1' MonControl='1' />  </Place></Area><Area id='园区' name='园区' code='10011002' LocationSetup='0'><Place id='科技园' name='科技园' code='100110011003' LocationSetup='1'><Monitor id='摄像头5' name='摄像头5' code='11000000000000000011200034800000' gesid='abcde5' channelid='1'  VideoScan='1'  Capture='1'  ManualREC='1'  RecPlay ='1' MonControl='1' />    <Monitor id='摄像头6' name='摄像头6' code='11000000000000000011200034800000' gesid='abcde6' channelid='1'  VideoScan='1'  Capture='1'  ManualREC='1'  RecPlay ='1' MonControl='1' />  </Place><Place id='金鸡湖' name='金鸡湖' code='100110011004' LocationSetup='2'><Monitor id='摄像头7' name='摄像头7' code='11000000000000000011200034800000' gesid='abcde7' channelid='1'  VideoScan='1'  Capture='1'  ManualREC='1'  RecPlay ='1' MonControl='1' />    <Monitor id='摄像头8' name='摄像头8' code='11000000000000000011200034800000' gesid='abcde8' channelid='1'  VideoScan='1'  Capture='1'  ManualREC='1'  RecPlay ='1' MonControl='1' />  </Place></Area></City></GESInfo>";
        xmldoc.Load(new System.IO.MemoryStream(System.Text.Encoding.GetEncoding("GB2312").GetBytes(info )));
        return xmldoc;
    }