程序中原来只记录一个日志，现在我要写一个用户操作日志，需要与原来的日志分开，在config文件中一阵折腾无果(要么写不全，要么写重了，反正没办法完美分离，要么与现存代码没办法完美兼容)，差点放弃准备自己直接写txt文件了。

在网上看到可以写自定义filter，可以and可以or，那还有什么事情是搞不定的呢？ 代码比较简单，不解释。

public class AndFilter : FilterSkeleton    {        private bool acceptOnMatch;        private readonly IList
     
       filters = new List
      
       ();        public override FilterDecision Decide(LoggingEvent loggingEvent)        {            if (loggingEvent == null)                throw new ArgumentNullException("loggingEvent");            foreach (IFilter filter in filters)            {                if (filter.Decide(loggingEvent) != FilterDecision.Accept)                    return FilterDecision.Neutral; // one of the filter has failed            }            return FilterDecision.Accept;        }        public IFilter Filter        {            set { filters.Add(value); }        }        public bool AcceptOnMatch        {            get { return acceptOnMatch; }            set { acceptOnMatch = value; }        }    }    public class OrFilter : FilterSkeleton    {        private bool acceptOnMatch;        private readonly IList
       
         filters = new List
        
         ();        public override FilterDecision Decide(LoggingEvent loggingEvent)        {            if (loggingEvent == null)                throw new ArgumentNullException("loggingEvent");            foreach (IFilter filter in filters)            {                if (filter.Decide(loggingEvent) == FilterDecision.Accept)                    return FilterDecision.Accept;            }            return FilterDecision.Deny;        }        public IFilter Filter        {            set { filters.Add(value); }        }        public bool AcceptOnMatch        {            get { return acceptOnMatch; }            set { acceptOnMatch = value; }        }    }
        
       
      
     

public partial class Test : System.Web.UI.Page    {        static ILog log = log4net.LogManager.GetLogger(typeof(Test));        static ILog logForSubmitStudentCode = log4net.LogManager.GetLogger("SubmitStudentCode");        static ILog logForUserAction = log4net.LogManager.GetLogger("UserAction");        protected void Page_Load(object sender, EventArgs e)        {            log.Fatal("Fatal");            log.Error("Error");            log.Warn("Warn");            log.Info("info");            logForSubmitStudentCode.Logger.Log(typeof(Test), new log4net.Core.Level(50000, "SubmitStudentCode"), "SubmitStudentCode test", null);            logForUserAction.Logger.Log(typeof(Test), new log4net.Core.Level(50001, "UserAction"), "UserAction test", null);        }    }