LogNet是一套开源的程序日志记录系统，经过配置后可以自动抓取程序中的错误、异常信息，并写入磁盘，也可以在异常发生时执行其他指定的操作，比如：通知某人右键、写入数据库等。
这里写个AspNet应用LogNet的Demo:
1.建立AspNet网站，在web.config中写LogNet的配置文件：
<?xml version="1.0"?><configuration> ???<configSections> ???????<section name="log4net" type="log4net.Config.Log4NetConfigurationSectionHandler,log4net"/> ???</configSections> ?????<log4net> ???????<!--错误日志配置--> ???????<appender name="ErrorAppender" type="log4net.Appender.RollingFileAppender"> ???????????<param name="File" value="Log\\LogError\\"/> ???<!--文件路径--> ???????????<param name="AppendToFile" value="true"/> ???????????<param name="MaxSizeRollBackups" value="100"/> ???????????<param name="MaxFileSize" value="10240"/> ???????????<param name="StaticLogFileName" value="false"/> ???????????<param name="DatePattern" value="yyyyMMdd"/> ???????????<param name="RollingStyle" value="Date"/> ???????????<layout type="log4net.Layout.PatternLayout"> ???????????????<param name="ConversionPattern" value="%n异常时间：%d [%t] %n异常级别：%-5p %n异 常 类：%c [%x] %n%m %n "/> ???????????</layout> ???????</appender> ???????<!--信息日志配置--> ???????<appender name="InfoAppender" type="log4net.Appender.RollingFileAppender"> ???????????<param name="File" value="Log\\LogInfo\\"/> ????<!--文件路径--> ???????????<param name="AppendToFile" value="true"/> ???????????<param name="MaxFileSize" value="10240"/> ???????????<param name="MaxSizeRollBackups" value="100"/> ???????????<param name="StaticLogFileName" value="false"/> ???????????<param name="DatePattern" value="yyyyMMdd"/> ???????????<param name="RollingStyle" value="Date"/> ???????????<layout type="log4net.Layout.PatternLayout"> ???????????????<param name="ConversionPattern" value="%n日志时间：%d [%t] %n日志级别：%-5p %n日 志 类：%c [%x] %n%m %n"/> ???????????</layout> ???????</appender> ???????<!--控制台--> ???????<appender name="ConsoleAppender" type="log4net.Appender.ConsoleAppender"> ???????????<layout type="log4net.Layout.PatternLayout"> ???????????????<conversionPattern value="%5level [%thread] (%file:%line) - %message%newline"/> ???????????</layout> ???????</appender> ???????<!--log4net.LogManager.GetLogger("logerror")用这个来选择这种类型--> ???????<logger name="logerror"> ???????????<level value="ERROR"/> ???????????<appender-ref ref="ErrorAppender"/> ???????</logger> ???<!--log4net.LogManager.GetLogger("loginfo")用这个来选择这种类型--> ???????<logger name="loginfo"> ???????????<level value="INFO"/> ???????????<appender-ref ref="InfoAppender"/> ???????</logger> ???????<root> ???????????<level value="INFO"/> ???????????<appender-ref ref="InfoAppender"/> ???????????<appender-ref ref="ConsoleAppender"/> ???????</root> ???</log4net> ???<system.web> ???????<compilation debug="true"/></system.web></configuration>2.建立日志记录Log类库，实现方法
/// <summary> ??????/// LogHelper的摘要说明。 ??????/// </summary> ??????public class LogHelper ???{ ???????private LogHelper() ???????{ ???????} ???????public static readonly log4net.ILog loginfo = log4net.LogManager.GetLogger("loginfo"); ??//选择<logger name="loginfo">的配置 ????????public static readonly log4net.ILog logerror = log4net.LogManager.GetLogger("logerror"); ??//选择<logger name="logerror">的配置 ????????/// <summary> ???????/// 默认配置。按配置文件 ???????/// </summary> ???????public static void SetConfig() ???????{ ???????????log4net.Config.XmlConfigurator.Configure(); ???????} ???????/// <summary> ???????/// 手动设置,作用未知 ???????/// </summary> ???????/// <param name="configFile"></param> ???????public static void SetConfig(FileInfo configFile) ???????{ ???????????log4net.Config.XmlConfigurator.Configure(configFile); ???????} ???????/// <summary> ???????/// 写信息。 ???????/// </summary> ???????/// <param name="info"></param> ???????public static void WriteLog(string info) ???????{ ???????????if (loginfo.IsInfoEnabled) ???????????{ ???????????????loginfo.Info(info); ???????????} ???????} ???????/// <summary> ???????/// 写日志。出错时会写入 ???????/// </summary> ???????/// <param name="info"></param> ???????/// <param name="se"></param> ???????public static void WriteLog(string info, Exception se) ???????{ ???????????if (logerror.IsErrorEnabled) ???????????{ ???????????????logerror.Error(info, se); ???????????} ???????} ???}3.在网站的Global.asax中配置网站与LogNet的联系。
public class Global : System.Web.HttpApplication ???{ ???????void Application_End(object sender, EventArgs e) ???????{ ???????????// ?在应用程序关闭时运行的代码 ???????} ???????void Session_Start(object sender, EventArgs e) ???????{ ???????????// 在新会话启动时运行的代码 ???????} ???????void Session_End(object sender, EventArgs e) ???????{ ???????????// 在会话结束时运行的代码。 ????????????// 注意: 只有在 Web.config 文件中的 sessionstate 模式设置为 ???????????// InProc 时，才会引发 Session_End 事件。如果会话模式设置为 StateServer ????????????// 或 SQLServer，则不会引发该事件。 ???????} ???????/// <summary> ???????/// 程序启动时配置lognet ???????/// </summary> ???????/// <param name="sender"></param> ???????/// <param name="e"></param> ???????protected void Application_Start(Object sender, EventArgs e) ???????{ ???????????//若不想把lognet配置文件写在web.config中，也可以另外手动指定。 ???????????//XmlConfigurator.Configure(new FileInfo(HttpContext.Current.Server.MapPath("~/App_Data/log4net.config"))); ???????} ???????/// <summary> ???????/// 程序出错时通过lognet写日志 ???????/// </summary> ???????/// <param name="sender"></param> ???????/// <param name="e"></param> ???????protected void Application_Error(Object sender, EventArgs e) ???????{ ???????????Exception objExp = HttpContext.Current.Server.GetLastError(); ???????????LogHelper.WriteLog("\r\n客户机IP:" + Request.UserHostAddress ????????????????+ "\r\n错误地址:" + Request.Url ????????????????+ "\r\n异常信息:" + Server.GetLastError().Message, objExp); ???????} ???}这样，当网站出错时，就会自动在网站目录的Log\LogError与LogInfo下写如文本日志。
LogNet4学习笔记
原文地址：https://www.cnblogs.com/weifeng123/p/8118167.html