摘要：
xmlversion="1.0"encoding="utf-8"?
1、新建Web或者Webform项目，使用Nuget下载log4net
2.新建Config文件夹，将log4net配置文件放入此文件夹中（当修改web.config的时候会重启网站，所以把log4net单独出来比较好，也好管理）， log4net的配置文件log4net_config.xml
在app.config或者web.config中的configuration节点下加入：放在configSections中第一位
<configSections> <section name="log4net" type="log4net.Config.Log4NetConfigurationSectionHandler,log4net"/> </configSections>
CS：
在Properties下的AssemblyInfo.cs文件中加入
[assembly: log4net.Config.XmlConfigurator(ConfigFile = "Config/log4net.config", Watch = true)]
如果我们将log4net帮助类放在另一个公共的类库项目中，又需要在另一个引用的项目中使用log4helper类，
这时候仅需要在该项目里的Properties下的AssemblyInfo.cs文件中加入这句：
[assembly: log4net.Config.XmlConfigurator(ConfigFile = "Config/log4net.config", Watch = true)]
日志配置：
第一种：
<?xml version="1.0" encoding="utf-8"?> <configuration> <system.web> <compilation debug="false" targetFramework="4.6.1" /> <httpRuntime targetFramework="4.6.1" /> </system.web> <log4net> <appender name="fatalAppender" type="log4net.Appender.RollingFileAppender"> <filter type="log4net.Filter.LevelMatchFilter"> <levelToMatch value="FATAL" /> </filter> <filter type="log4net.Filter.DenyAllFilter" /> <File value="Logsfatal.log" /> <appendToFile value="true" /> <rollingStyle value="Date" /> <datePattern value="yyyyMMdd" /> <layout type="log4net.Layout.PatternLayout"> <conversionPattern value="%date [%thread] %-5level %logger - %message%newline" /> </layout> </appender> <appender name="errorAppender" type="log4net.Appender.RollingFileAppender"> <filter type="log4net.Filter.LevelMatchFilter"> <levelToMatch value="ERROR" /> </filter> <filter type="log4net.Filter.DenyAllFilter" /> <File value="Logserr.log" /> <appendToFile value="true" /> <rollingStyle value="Date" /> <datePattern value="yyyyMMdd" /> <layout type="log4net.Layout.PatternLayout"> <conversionPattern value="%date [%thread] %-5level %logger - %message%newline" /> </layout> </appender> <appender name="warnAppender" type="log4net.Appender.RollingFileAppender"> <filter type="log4net.Filter.LevelMatchFilter"> <levelToMatch value="WARN" /> </filter> <filter type="log4net.Filter.DenyAllFilter" /> <File value="Logswarn.log" /> <appendToFile value="true" /> <rollingStyle value="Date" /> <datePattern value="yyyyMMdd" /> <layout type="log4net.Layout.PatternLayout"> <conversionPattern value="%date [%thread] %-5level %logger - %message%newline" /> </layout> </appender> <appender name="infoAppender" type="log4net.Appender.RollingFileAppender"> <filter type="log4net.Filter.LevelMatchFilter"> <levelToMatch value="INFO" /> </filter> <filter type="log4net.Filter.DenyAllFilter" /> <File value="Logsinfo.log" /> <appendToFile value="true" /> <rollingStyle value="Date" /> <datePattern value="yyyyMMdd" /> <layout type="log4net.Layout.PatternLayout"> <conversionPattern value="%date [%thread] %-5level %logger - %message%newline" /> </layout> </appender> <appender name="debugAppender" type="log4net.Appender.RollingFileAppender"> <filter type="log4net.Filter.LevelMatchFilter"> <levelToMatch value="DEBUG" /> </filter> <filter type="log4net.Filter.DenyAllFilter" /> <File value="Logsdebug.log" /> <appendToFile value="true" /> <rollingStyle value="Date" /> <datePattern value="yyyyMMdd" /> <layout type="log4net.Layout.PatternLayout"> <conversionPattern value="%date [%thread] %-5level %logger - %message%newline" /> </layout> </appender> <appender name="perfAppender" type="log4net.Appender.RollingFileAppender"> <filter type="log4net.Filter.LevelMatchFilter"> <levelToMatch value="INFO" /> </filter> <filter type="log4net.Filter.DenyAllFilter" /> <File value="Logsperf.log" /> <appendToFile value="true" /> <rollingStyle value="Date" /> <datePattern value="yyyyMMdd" /> <layout type="log4net.Layout.PatternLayout"> <conversionPattern value="%date %logger - %message%newline" /> </layout> </appender> <root> <level value="ALL" /> <appender-ref ref="fatalAppender" /> <appender-ref ref="errorAppender" /> <appender-ref ref="warnAppender" /> <appender-ref ref="infoAppender" /> <appender-ref ref="debugAppender" /> </root> </log4net> </configuration>
第二种： 可以放在configuration种
<log4net>
<appender name="fatalAppender" type="log4net.Appender.RollingFileAppender">
<filter type="log4net.Filter.LevelMatchFilter">
<levelToMatch value="FATAL" />
</filter>
<filter type="log4net.Filter.DenyAllFilter" />
<File value="LogsFatalfatal.log" />
<appendToFile value="true" />
<rollingStyle value="Date" />
<datePattern value="yyyyMMdd" />
<layout type="log4net.Layout.PatternLayout">
<conversionPattern value="%date [%thread] %-5level %logger - %message%newline" />
</layout>
</appender>
<!-- 错误日志附加介质-->
<appender name="errorAppender" type="log4net.Appender.RollingFileAppender">
<filter type="log4net.Filter.LevelMatchFilter">
<levelToMatch value="ERROR" />
</filter>
<filter type="log4net.Filter.DenyAllFilter" />
<param name="File" value="Log\" />
<param name="AppendToFile" value="true" />
<param name="MaxSizeRollBackups" value="100" />
<param name="MaxFileSize" value="10240" />
<param name="StaticLogFileName" value="false" />
<param name="DatePattern" value="Error/yyyy-MM-dd/"Error_"yyyyMMdd".log"" />
<param name="RollingStyle" value="Date" />
<!-- 信息日志布局-->
<layout type="log4net.Layout.PatternLayout">
<!--<conversionPattern value="%date [%thread] %-5level %logger - %message%newline" />-->
<param name="ConversionPattern" value="记录时间：%date 线程ID:[%thread] 日志级别：%-5level 记录类：%logger 操作者ID：%property{Operator} 操作类型：%property{Action}%n 当前机器名:%property%n当前机器名及登录用户：%username %n 记录位置：%location%n 消息描述：%property{Message}%n 异常：%exception%n 消息：%message%newline%n%n" />
</layout>
</appender>
<appender name="warnAppender" type="log4net.Appender.RollingFileAppender">
<filter type="log4net.Filter.LevelMatchFilter">
<levelToMatch value="WARN" />
</filter>
<filter type="log4net.Filter.DenyAllFilter" />
<File value="LogsWarnwarn.log" />
<appendToFile value="true" />
<rollingStyle value="Date" />
<datePattern value="yyyyMMdd" />
<layout type="log4net.Layout.PatternLayout">
<conversionPattern value="%date [%thread] %-5level %logger - %message%newline" />
</layout>
</appender>
<appender name="infoAppender" type="log4net.Appender.RollingFileAppender">
<filter type="log4net.Filter.LevelMatchFilter">
<levelToMatch value="INFO" />
</filter>
<filter type="log4net.Filter.DenyAllFilter" />
<File value="LogsInfoinfo.log" />
<appendToFile value="true" />
<rollingStyle value="Date" />
<datePattern value="yyyyMMdd" />
<layout type="log4net.Layout.PatternLayout">
<conversionPattern value="%date [%thread] %-5level %logger - %message%newline" />
</layout>
</appender>
<appender name="debugAppender" type="log4net.Appender.RollingFileAppender">
<filter type="log4net.Filter.LevelMatchFilter">
<levelToMatch value="DEBUG" />
</filter>
<filter type="log4net.Filter.DenyAllFilter" />
<File value="LogsDebugdebug.log" />
<appendToFile value="true" />
<rollingStyle value="Date" />
<datePattern value="yyyyMMdd" />
<layout type="log4net.Layout.PatternLayout">
<conversionPattern value="%date [%thread] %-5level %logger - %message%newline" />
</layout>
</appender>
<appender name="perfAppender" type="log4net.Appender.RollingFileAppender">
<filter type="log4net.Filter.LevelMatchFilter">
<levelToMatch value="INFO" />
</filter>
<filter type="log4net.Filter.DenyAllFilter" />
<File value="Logsperf.log" />
<appendToFile value="true" />
<rollingStyle value="Date" />
<datePattern value="yyyyMMdd" />
<layout type="log4net.Layout.PatternLayout">
<conversionPattern value="%date %logger - %message%newline" />
</layout>
</appender>
<root>
<level value="ALL" />
<appender-ref ref="fatalAppender" />
<appender-ref ref="errorAppender" />
<appender-ref ref="warnAppender" />
<appender-ref ref="infoAppender" />
<appender-ref ref="debugAppender" />
</root>
</log4net>第三个示例
<log4net>
<!-- OFF, FATAL, ERROR, WARN, INFO, DEBUG, ALL -->
<!-- Set root logger level to ERROR and its appenders -->
<root>
<level value="ALL" />
<appender-ref ref="SysAppender" />
</root>
<!-- Print only messages of level DEBUG or above in the packages -->
<logger name="WebLogger">
<level value="DEBUG" />
</logger>
<appender name="SysAppender" type="log4net.Appender.RollingFileAppender,log4net">
<param name="File" value="App_Data/" />
<param name="AppendToFile" value="true" />
<param name="RollingStyle" value="Date" />
<param name="DatePattern" value=""Logs_"yyyyMMdd".txt"" />
<param name="StaticLogFileName" value="false" />
<layout type="log4net.Layout.PatternLayout,log4net">
<param name="ConversionPattern" value="%d [%t] %-5p %c - %m%n" />
</layout>
</appender>
<appender name="consoleApp" type="log4net.Appender.ConsoleAppender,log4net">
<layout type="log4net.Layout.PatternLayout,log4net">
<param name="ConversionPattern" value="%d [%t] %-5p %c - %m%n" />
</layout>
</appender>
</log4net>3. 在项目中
log4net.ILog log = LogManager.GetLogger("log---"); //"log---" 会在日志文件中显示 log4net.Config.XmlConfigurator.Configure(); //--这个执行一次就可以 log4net.config //配置log4--单独放一个文件中的 //log4net.Config.XmlConfigurator.Configure(new System.IO.FileInfo(Server.MapPath("~/log4net.config"))); log.Info(DateTime.Now + "这是一个log4net提示日志"); log.Error(DateTime.Now + "log4net错误日志");
4. 日志记录到数据库
<?xml version="1.0" encoding="utf-8" ?> <log4net debug="false"> <!-- name属性指定其名称,type则是log4net.Appender命名空间的一个类的名称,意思是,指定使用哪种介质--> <appender name="ADONetAppender" type="log4net.Appender.ADONetAppender"> <!--日志缓存写入条数 设置为0时只要有一条就立刻写到数据库--> <bufferSize value="0" /> <!--日志数据库连接串--> <connectionType value="System.Data.SqlClient.SqlConnection, System.Data, Version=1.0.5000.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" /> <connectionString value="DATABASE=GoodLook;SERVER=xx.xx.140.170;UID=sa;PWD=123456a;Connect Timeout=30;" /> <!--日志数据库脚本--> <commandText value="INSERT INTO LogDetails ([LogDate],[LogThread],[LogLevel],[LogLogger],[LogActionClick],[LogMessage],[UserName],[UserIP]) VALUES (@log_date, @thread, @log_level, @logger, @ActionsClick, @message,@UserName,@UserIP)" /> <!--日志时间LogDate --> <parameter> <parameterName value="@log_date" /> <dbType value="DateTime" /> <layout type="log4net.Layout.RawTimeStampLayout" /> </parameter> <!--线程号--> <parameter> <parameterName value="@thread" /> <dbType value="String" /> <size value="100" /> <layout type="log4net.Layout.PatternLayout"> <conversionPattern value="%t" /> </layout> </parameter> <!--日志类型LogLevel --> <parameter> <parameterName value="@log_level" /> <dbType value="String" /> <size value="200" /> <layout type="log4net.Layout.PatternLayout"> <conversionPattern value="%p" /> </layout> </parameter> <!--日志名称--> <parameter> <parameterName value="@logger" /> <dbType value="String" /> <size value="500" /> <layout type="log4net.Layout.PatternLayout"> <conversionPattern value="%logger" /> </layout> </parameter> <parameter> <parameterName value="@message" /> <dbType value="String" /> <size value="3000" /> <layout type="Log4NetApply.MyLayout"> <conversionPattern value="%property{Message}" /> </layout> </parameter> <parameter> <parameterName value="@ActionsClick" /> <dbType value="String" /> <size value="4000" /> <layout type="Log4NetApply.MyLayout" > <conversionPattern value = "%property{ActionsClick}"/> </layout> </parameter> <!--自定义UserName --> <parameter> <parameterName value="@UserName" /> <dbType value="String" /> <size value="30" /> <layout type="Log4NetApply.MyLayout" > <!--log4net.MDC.Set("UserName", "asdfasdf"); <conversionPattern value = "%X{UserName}"/>--> <conversionPattern value = "%property{UserName}"/> </layout> </parameter> <parameter> <parameterName value="@UserIP" /> <dbType value="String" /> <size value="20" /> <layout type="Log4NetApply.MyLayout" > <conversionPattern value = "%property{UserIP}"/> </layout> </parameter> </appender> <!-- setup the root category, add the appenders and set the default level --> <root> <level value="Warn"/><!-- 定义记录的日志级别--> <level value="Info"/> <level value="Debug"/> <level value="Fine"/> <appender-ref ref="ADONetAppender" /><!-- 记录到什么介质中--> </root> <!-- specify the level for some specific categories --> <!--//关于上边root到logger这块，如果同时出现，有可能会出现重复插入记录的情况：--> <!--<logger name="iNotes"> <level value="WARN"/> <level value="INFO"/> <level value="DEBUG"/> <level value="FINE"/> <appender-ref ref="ADONetAppender"/> </logger> <logger name="StellaLogger"> <level value="ALL"/> <appender-ref ref="AdoNetAppender" /> </logger>--> <appender name="ReflectionLayout" type="log4net.Appender.RollingFileAppender,log4net"> <!--日志文件路径,按文件大小方式输出时在这里指定文件名，并且前面的日志按天在文件名后自动添加当天日期形成文件--> <param name="File" value="D:/Log/" /> <!--是否追加到文件--> <param name="AppendToFile" value="true" /> <!--记录日志写入文件时，不锁定文本文件--> <!--<lockingModel type="log4net.Appender.FileAppender+MinimalLock" />--> <!--Unicode编码--> <!--<Encoding value="UTF-8" />--> <!--最多产生的日志文件数，value="－1"为不限文件数--> <!--<param name="MaxSizeRollBackups" value="10" />--> <!--是否只写到一个文件中--> <param name="StaticLogFileName" value="false" /> <!--按照何种方式产生多个日志文件(日期[Date],文件大小[Size],混合[Composite])--> <param name="RollingStyle" value="Composite" /> <!--按日期产生文件夹，文件名［在日期方式与混合方式下使用］--> <param name="DatePattern" value="yyyy-MM-dd/"ReflectionLayout.log"" /> <!--<param name="DatePattern" value="yyyyMMdd/yyyyMMdd"-TimerServer.log"" />--> <!--<param name="DatePattern" value="yyyyMMdd/"TimerServer/TimerServer.log"" />--> <!--每个文件的大小。只在混合方式与文件大小方式下使用，超出大小的在文件名后自动增加1重新命名--> <param name="maximumFileSize" value="500KB" /> <!--记录的格式。--> <layout type="TGLog.ExpandLayout2.ReflectionLayout,TGLog"> <param name="ConversionPattern" value="记录时间：%date 线程ID:[%thread] 日志级别：%-5level 记录类：%logger 操作者ID：%property{Operator} 操作类型：%property{Action}%n 当前机器名:%property%n当前机器名及登录用户：%username %n 记录位置：%location%n 消息描述：%property{Message}%n 异常：%exception%n 消息：%message%newline%n%n" /> </layout> </appender> </log4net>
<bufferSize value="10" />,表示是记录10 条到缓冲区，满10条后再写入SQL server 调试时可以改为1，实际应用建议为100 <root> <level value="WARN"/> <level value="INFO"/> <level value="DEBUG"/> <level value="FINE"/> <appender-ref ref="ADONetAppender" /> </root> 在需要记录的每个类中添加如下代码： private static log4net.ILog myLogger = log4net.LogManager.GetLogger(System.Reflection.MethodBase.GetCurrentMethod().DeclaringType);
https://blog.csdn.net/kongwei521/article/details/52242319
https://www.cnblogs.com/daretodream/p/3509027.html
另外：可以找log4net帮助类
链接：https://www.cnblogs.com/weixiaowei/p/8253228.html