void Main()
{
    XDocument xml=XDocument.Load("c:\\test.xml");
    var query=from x in xml.Descendants("server") 
              select new{name=x.Element("name").Value,server_id=x.Element("server_id").Value};
    foreach(var q in query)
    {
      Console.WriteLine("Name:{0}\tServerId:{1}",q.name,q.server_id);
    }
      /*
        Name:张三    ServerId:1
        Name:李四    ServerId:2
        Name:王五    ServerId:3

      */
}