读取XML配置文件.
麻烦各位高手指点一二..多谢!

这是XML文件读取类.
public class Cls_ConfigReader : System.Web.UI.Page
{
     private static XmlDocument xmldoc;

      public static void ConfigReader(string xmlFile)
        {
            xmldoc = new XmlDocument();
            xmldoc.Load(HttpContext.Current.Server.MapPath(@"~/" + xmlFile));
        }
 public static List<Cls_Goods> wb_getGoodsInfo(string _ucode)
        {
            List<Cls_Goods> mylist = null;
            try
            {
                XmlNode xnode = xmldoc.SelectSingleNode("userconfig/user[@code='" + _ucode.ToUpper() + "']");
                if (xnode != null)
                {
                    mylist = new List<Cls_Goods>();
                    XmlNodeList ndlist = xnode.SelectNodes("goodsconfig/goods");
                    foreach (XmlNode nd in ndlist)
                    {
                        Cls_Goods goods = new Cls_Goods();
                        goods.TradeCodeOnLine = nd.Attributes["code"].Value;
                        goods.ExchangeCode = nd.Attributes["excode"].Value;
                        goods.TradeName = nd.InnerText;
                        mylist.Add(goods);
                    }
                }
            }
            catch
            {
                throw new Exception("请检查配置文件!");
            }
            return mylist;
        }
 public static List<Cls_Title> wb_getTitle(string _ucode)
        {
            List<Cls_Title> titles = null;
            try
            {
                //得到当前用户的配置节点
                XmlNode xnode = xmldoc.SelectSingleNode("userconfig/user[@code='" + _ucode.ToUpper() + "']");
                if (xnode != null)
                {
                    titles = new List<Cls_Title>();
                    XmlNodeList ndlist = xnode.SelectNodes("titles/title");
                    foreach (XmlNode nd in ndlist)
                    {
                        Cls_Title title = new Cls_Title();
                        title.titlename = nd.InnerText;
                        title.titlecode = nd.Attributes["code"].Value;
                        titles.Add(title);
                    }
                }
            }
            catch
            {

                throw new Exception("请检查配置文件！");
            }

            return titles;
        }
}

下面是其中两个调用XML读取类的方法

 public static Cls_UserInfo GetUserInfo(string userid,string xmlFile)
        {
            string thekey = userid + "---Cls_UserInfo---" + CODE_CACHE_KEY + "---GetUserInfo---" + xmlFile;
            Cls_UserInfo user = null;
            rwlock.AcquireReaderLock(Timeout.Infinite);
            try
            {
                if (HttpContext.Current.Cache[thekey] != null)
                {
                    user = (Cls_UserInfo)HttpContext.Current.Cache[thekey];
                }
                else
                {
                    LockCookie lc = rwlock.UpgradeToWriterLock(Timeout.Infinite);
                    try
                    {
                        for (int i = 0; i < 5; i++)
                        {
                            if ( user == null)
                            {
                                Cls_ConfigReader.ConfigReader(xmlFile);
                                user = Cls_ConfigReader.wb_getUserInfo(userid);
                            }
                        }
                        if (user != null)
                        {
                            HttpContext.Current.Cache.Insert(thekey, user, null, DateTime.Now.AddSeconds(CACHE_Min), System.Web.Caching.Cache.NoSlidingExpiration);
                        }

                    }
                    finally
                    {
                        rwlock.DowngradeFromWriterLock(ref lc);
                    }
                }
                return user;
            }
            finally
            {
                rwlock.ReleaseReaderLock();
            }
        }


 public static List<Cls_Title> GetUserTitleInfo(string userid, string xmlFile)
        {
            string thekey = userid + "List<Cls_Title>" + CODE_CACHE_KEY + "GetUserTitleInfo" + xmlFile;
            List<Cls_Title> titlelist = null;
            rwlock.AcquireReaderLock(Timeout.Infinite);
            try
            {
                if (HttpContext.Current.Cache[thekey] != null)
                {
                    titlelist = (List<Cls_Title>)HttpContext.Current.Cache[thekey];
                }
                else
                {
                    LockCookie lc = rwlock.UpgradeToWriterLock(Timeout.Infinite);
                    try
                    {
                        for (int i = 0; i < 5; i++)
                        {
                            if (titlelist == null )
                            {
                                Cls_ConfigReader.ConfigReader(xmlFile);
                                titlelist = Cls_ConfigReader.wb_getTitle(userid);
                            }
                        }
                        if (titlelist != null)
                        {
                            HttpContext.Current.Cache.Insert(thekey, titlelist, null, DateTime.Now.AddSeconds(CACHE_Min), System.Web.Caching.Cache.NoSlidingExpiration);
                        }
                    }
                    finally
                    {
                        rwlock.DowngradeFromWriterLock(ref lc);
                    }
                }

                return titlelist;

            }
            finally
            {
                rwlock.ReleaseReaderLock();
            }
        }

出的问题比较奇怪.有时候出现

1.此文档已具有 'XmlDeclaration' 节点。

2.有时候读取XML文件的方法出现获取为空,比如 GetUserInfo 方法 返回 Cls_UserInfo user 对象.这个user有时候就为空.

GetUserTitleInfo 方法 返回List<Cls_Title> titlelist,这个titlelist就为空.

有时候出现一次,刷新一次又好了..一直找不到问题所在..

方法里面的缓存键也是唯一的,根据不同的方法名,用户名,和配置文件名称组成的缓存键..



中间的  for (int i = 0; i < 5; i++)
也是后来弄的没办法了才加上去的,后来报错次数比以前少了,不过还是会有报.