log4net教程日志分类和自动维护示例

public static ILog GetLogger(string repositoryName = "")
        {
            if (string.IsNullOrEmpty(repositoryName)) return LogManager.GetLogger("Defalut");

            ILoggerRepository repository = null;
            try
            {
                repository = LogManager.GetRepository(repositoryName);
            }
            catch (Exception) { }

            //找到直接返回ilog
            if (repository != null)
                return LogManager.GetLogger(repositoryName, "Defalut");

            //未找到则创建，多线程下很有可能创建时，就存在了
            try
            {
                repository = LogManager.CreateRepository(repositoryName);
            }
            catch (Exception)
            {
                repository = LogManager.GetRepository(repositoryName);
            }

            //配置日志等级  读取Appsettings默认配置 
            var appSet = ConfigurationManager.AppSettings.AllKeys;

            //查找日志等级
            const string logLevel = "LogLevel";
            var hasSettings = Array.IndexOf(appSet, logLevel);
            if (hasSettings > -1)
            {
                var level = ConfigurationManager.AppSettings[logLevel].ToLower();
                if (level == "all") repository.Threshold = Level.All;
                else if (level == "debug") repository.Threshold = Level.Debug;
                else if (level == "info") repository.Threshold = Level.Info;
                else if (level == "warn") repository.Threshold = Level.Warn;
                else if (level == "error") repository.Threshold = Level.Error;
                else if (level == "fatal") repository.Threshold = Level.Fatal;
                else if (level == "off") repository.Threshold = Level.Off;
            }
            else repository.Threshold = Level.All;

            //查找输出Appender
            const string logAppender = "LogAppender";
            hasSettings = Array.IndexOf(appSet, logAppender);
            if (hasSettings > -1)
            {
                var appenders = ConfigurationManager.AppSettings[logAppender].ToLower().Split(',');
                foreach (var appender in appenders)
                {
                    if (appender == "rollingfile") LoadRollingFileAppender(repository);
                    else if (appender == "console") LoadConsoleAppender(repository);
                    else if(appender == "trace") LoadTraceAppender(repository);
                }
            }
            else LoadRollingFileAppender(repository);

            return LogManager.GetLogger(repositoryName, "Default");
        }

<!--RollingFileAppender:输出到文件中-->
    <appender name="SysAppender" type="log4net.Appender.RollingFileAppender">
      <!--日志的路径-->
      <file value="Logs/" />
      <!--是否覆盖，默认是追加true-->
      <appendToFile value="true"/>
      <!--不占用日志文件进程-->
      <lockingModel type="log4net.Appender.FileAppender+MinimalLock" />
      <rollingStyle value="Composite"/>
      <!--文件名称-->
      <DatePattern value="yyyy-MM-dd HH'时.log'"></DatePattern>
      <!--设置无限备份=-1 ，最大备份数为1000-->
      <param name="MaxSizeRollBackups" value="1000"/>
      <!--每个文件的大小-->
      <param name="MaximumFileSize" value="500KB"/>
      <!--名称是否可以更改 为false为可以更改-->
      <param name="StaticLogFileName" value="false"/>
      <layout type="log4net.Layout.PatternLayout">
        <!--输出格式-->
        <conversionPattern value="%n【记录时间】%date%n【描述】%message%n"/>
      </layout>
    </appender>

<!--RollingFileAppender:输出到文件中-->
    <appender name="SysAppender" type="log4net.Appender.RollingFileAppender">
      <!--日志的路径-->
      <file value="Logs/日志.log" />
      <!--是否覆盖，默认是追加true-->
      <appendToFile value="true"/>
      <!--不占用日志文件进程-->
      <lockingModel type="log4net.Appender.FileAppender+MinimalLock" />
      <rollingStyle value="Composite"/>
      <!--文件名称-->
      <DatePattern value="yyyy-MM-dd HH'时.log'"></DatePattern>
      <!--设置无限备份=-1 ，最大备份数为1000-->
      <param name="MaxSizeRollBackups" value="1000"/>
      <!--每个文件的大小-->
      <param name="MaximumFileSize" value="500KB"/>
      <!--名称是否可以更改 为false为可以更改-->
      <param name="StaticLogFileName" value="true"/>
      <layout type="log4net.Layout.PatternLayout">
        <!--输出格式-->
        <conversionPattern value="%n【记录时间】%date%n【描述】%message%n"/>
      </layout>
    </appender>