新手求读取xml节点的有关问题

新手求读取xml节点的问题，
<TcEventSources>
<Source>
<Id>50</Id>
<Name>TwinCAT Cnc Errors</Name>
<Event>
<Id>1</Id>
<ReqMustCon>0</ReqMustCon>
<Message LcId="2052">急停报警</Message>
<Class>7</Class>
<Priority>0</Priority>
</Event>
<Event>
<Id>2</Id>
<ReqMustCon>0</ReqMustCon>
<Message LcId="2052">普通报警</Message>
<Class>7</Class>
<Priority>0</Priority>
</Event>
</Source>
</TcEventSources>

读取ID  1 或者 2 的急停报警 ，普通报警，之前用的
 XmlNodeList xmlNodeList = xmlDoc.SelectNodes("TcEventSources/Source/Event" + "[id='" + id + "']");//查找
            XmlNode xmlNode = xmlNodeList.Item(0);
            return xmlNode["Class"].InnerText;
            //XmlNode xmlNode = xmlNodeList.Item(0);
            //return xmlNode["id"].InnerText;//   "TcEventSources/Source/Event" + id 

都不对  谢谢大神的指教
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XPATH要逐级查找，不能跳级
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请为参加博客之星的我投上一票感激之至
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http://blog.****.net/duanzi_peng/article/details/24018431
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使用LINQ TO XML。
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XmlNodeList xmlNodeList = xmlDoc.SelectNodes("TcEventSources/Source/Event" + "[id='" + id + "']");//查找
            XmlNode xmlNode = xmlNodeList.ChildNodes[2].InnerText;
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 XDocument item = XDocument.Load("test1.xml");

            var result = from x in item.Descendants("Event")

                         select new

                         {

                             ID = x.Element("Id").Value,

                             Message = x.Element("Message").Value,

                          

                         };

            foreach (var el in result)

            {

                MessageBox.Show(el.ID + " " + el.Message );

            }

------解决思路----------------------
 XmlDocument xmlDoc = new XmlDocument();
            try
            {
                xmlDoc.Load(filename);                
                XmlNodeList xList = xmlDoc.SelectNodes("//Event");
                foreach (XmlNode x in xList)
                {
                    string Id = (x.SelectSingleNode("Id")).InnerText;
                    string Message = (x.SelectSingleNode("Message ")).InnerText;
                    
                }
            }
            catch (Exception e)
            {               
            }