一.组件引用
1.首先nuget中引入log4net
2.项目AssemblyInfo.cs引入log4net, 文件路径：项目/Properties/AssemblyInfo.cs
注：如果不在此引入直接在global中引入，在不部署到IIS中时本地测试是可以用的，如果要部署到IIS中则需要添加，请注意。
3.global中引入
log4net.Config.XmlConfigurator.Configure(new System.IO.FileInfo("log4net.config"));二.log4net.config配置
1.写入文件
注意：如果是有多个appender写文件配置，如果记录则会同时写入多个appender指定的文件中，如需解决此问题，需要看底层代码重写，目前暂时用不到所以没去处理。
<?xml version="1.0" encoding="utf-8" ?><configuration> ?<configSections> ???<section name="log4net" type="log4net.Config.Log4NetConfigurationSectionHandler, log4net"/> ?</configSections> ?<system.web> ???<compilation debug="true" targetFramework="4.0" /> ?</system.web> ?<log4net> ???<!--定义输出到文件中--> ???<appender name="RollingLogFileAppender" type="log4net.Appender.RollingFileAppender"> ?????<!--输出文件路径--> ?????<file type="log4net.Util.PatternString" ?value="Log/%date{yyyy}/%date{yyyyMM}/"/> ?????<appendToFile value="true"/> ?????<rollingStyle value="Date"/> ?????<datePattern value="yyyyMMdd‘.txt‘"/> ?????<staticLogFileName value="false"/> ?????<param name="MaxSizeRollBackups" value="100"/> ?????<layout type="log4net.Layout.PatternLayout"> ???????<!--每条日志末尾的文字说明--> ???????<!--输出格式--> ???????<conversionPattern value="%newline %n记录时间：%date %n线程ID:[%thread] %n日志级别： ?%-5level %n类：%logger property: [%property{NDC}] - %n描述：%message%newline %n"/> ?????</layout> ???</appender> ???<root> ?????<!--(高) OFF > FATAL > ERROR > WARN > INFO > DEBUG > ALL (低) --> ?????<level value="ALL"/> ?????<!--文件形式记录日志--> ?????<appender-ref ref="RollingLogFileAppender"/> ???</root> ?</log4net></configuration>2.写入数据库
注意点：
- 写入数据库appender type类型为：log4net.Appender.AdoNetAppender
- 可以为多种级别信息创建不同的appender，以name区分
- 请注意每添加一个appender，需要增加过滤器用于识别logger,同时需要增加DenyAllFilter，防止其他appender也插入日志，loggerToMatch中value对应代码中 logger别名。
<filter type="log4net.Filter.LoggerMatchFilter"> ???????<loggerToMatch value="gops" /> ?</filter> <filter type="log4net.Filter.DenyAllFilter" />
LogHelper类：
/// <summary> ???/// 日志辅助类 ???/// </summary> ??public class LogHelper ???{ ??????private static log4net.ILog log = null; ??????static LogHelper() ??????{ ??????????log = log4net.LogManager.GetLogger("gops"); ??????} ??????/// <summary> ??????/// 普通日志 ??????/// </summary> ??????/// <param name="content"></param> ??????public static void Info(string content) ??????{ ??????????try ??????????{ ??????????????log.Info(content); ??????????} ??????????catch { } ??????} ??????/// <summary> ??????/// 调试日志 ??????/// </summary> ??????/// <param name="content"></param> ??????public static void Debug(string content, Exception ex = null) ??????{ ??????????try ??????????{ ??????????????log.Debug(content,ex); ??????????} ??????????catch { } ??????} ??????/// <summary> ??????/// 错误日志 ??????/// </summary> ??????/// <param name="content"></param> ??????public static void Error(string content,Exception ex=null) ??????{ ??????????try ??????????{ ??????????????log.Error(content,ex); ??????????} ??????????catch { } ??????} ??????/// <summary> ??????/// 严重错误日志 ??????/// </summary> ??????/// <param name="content"></param> ??????public static void Fatal(string content, Exception ex = null) ??????{ ??????????try ??????????{ ??????????????log.Fatal(content,ex); ??????????} ??????????catch { } ??????} ??????/// <summary> ??????/// 警告日志 ??????/// </summary> ??????/// <param name="content"></param> ??????public static void Warn(string content, Exception ex = null) ??????{ ??????????try ??????????{ ??????????????log.Warn(content,ex); ??????????} ??????????catch { } ??????} ???}完整代码：
<?xml version="1.0" encoding="utf-8" ?><configuration> ?<configSections> ???<section name="log4net" type="log4net.Config.Log4NetConfigurationSectionHandler, log4net"/> ?</configSections> ?<system.web> ???<compilation debug="true" targetFramework="4.0" /> ?</system.web> ?<log4net> ???<!--<appender name="AdoNetAppender" type="log4net.Appender.AdoNetAppender"> ?????<bufferSize value="1" /> ?????<connectionType value="System.Data.SqlClient.SqlConnection,System.Data, Version=2.0.0.0, Culture=neutral,PublicKeyToken=b77a5c561934e089" /> ?????<connectionString value="数据库连接" /> ?????<commandText value="INSERT INTO Log ([Date],[Thread],[Level],[Logger],[Message],[Exception]) VALUES (@log_date, @thread, @log_level, @logger, @message, @exception)" /> ?????<parameter> ???????<parameterName value="@log_date" /> ???????<dbType value="DateTime" /> ???????<layout type="log4net.Layout.RawTimeStampLayout" /> ?????</parameter> ?????<parameter> ???????<parameterName value="@thread" /> ???????<dbType value="String" /> ???????<size value="255" /> ???????<layout type="log4net.Layout.PatternLayout"> ?????????<conversionPattern value="%thread" /> ???????</layout> ?????</parameter> ?????<parameter> ???????<parameterName value="@log_level" /> ???????<dbType value="String" /> ???????<size value="50" /> ???????<layout type="log4net.Layout.PatternLayout"> ?????????<conversionPattern value="%level" /> ???????</layout> ?????</parameter> ?????<parameter> ???????<parameterName value="@logger" /> ???????<dbType value="String" /> ???????<size value="255" /> ???????<layout type="log4net.Layout.PatternLayout"> ?????????<conversionPattern value="%logger" /> ???????</layout> ?????</parameter> ?????<parameter> ???????<parameterName value="@message" /> ???????<dbType value="String" /> ???????<size value="4000" /> ???????<layout type="log4net.Layout.PatternLayout"> ?????????<conversionPattern value="%message" /> ???????</layout> ?????</parameter> ?????<parameter> ???????<parameterName value="@exception" /> ???????<dbType value="String" /> ???????<size value="2000" /> ???????<layout type="log4net.Layout.ExceptionLayout" /> ?????</parameter> ?????<filter type="log4net.Filter.LoggerMatchFilter"> ???????<loggerToMatch value="gops1" /> ?????</filter> ?????<filter type="log4net.Filter.DenyAllFilter" /> ???</appender>--> ???<!--接口日志--> ???<appender name="AdoNetAppender" type="log4net.Appender.AdoNetAppender"> ?????<bufferSize value="1" /> ?????<connectionType value="System.Data.SqlClient.SqlConnection,System.Data, Version=2.0.0.0, Culture=neutral,PublicKeyToken=b77a5c561934e089" /> ?????<connectionString value="数据库连接" /> ?????<commandText value="execute LogInsert @tablename,@thread,@log_level,@logger,@message,@exception" /> ?????<parameter> ???????<parameterName value="@tablename" /> ???????<dbType value="String" /> ???????<layout type="log4net.Layout.PatternLayout"> ?????????<conversionPattern value="%date{OpenApiyyyyMM}" /> ???????</layout> ?????</parameter> ?????<parameter> ???????<parameterName value="@log_date" /> ???????<dbType value="DateTime" /> ???????<layout type="log4net.Layout.RawTimeStampLayout" /> ?????</parameter> ?????<parameter> ???????<parameterName value="@thread" /> ???????<dbType value="String" /> ???????<size value="255" /> ???????<layout type="log4net.Layout.PatternLayout"> ?????????<conversionPattern value="%thread" /> ???????</layout> ?????</parameter> ?????<parameter> ???????<parameterName value="@log_level" /> ???????<dbType value="String" /> ???????<size value="50" /> ???????<layout type="log4net.Layout.PatternLayout"> ?????????<conversionPattern value="%level" /> ???????</layout> ?????</parameter> ?????<parameter> ???????<parameterName value="@logger" /> ???????<dbType value="String" /> ???????<size value="255" /> ???????<layout type="log4net.Layout.PatternLayout"> ?????????<conversionPattern value="%logger" /> ???????</layout> ?????</parameter> ?????<parameter> ???????<parameterName value="@message" /> ???????<dbType value="String" /> ???????<size value="4000" /> ???????<layout type="log4net.Layout.PatternLayout"> ?????????<conversionPattern value="%message" /> ???????</layout> ?????</parameter> ?????<parameter> ???????<parameterName value="@exception" /> ???????<dbType value="String" /> ???????<size value="2000" /> ???????<layout type="log4net.Layout.ExceptionLayout" /> ?????</parameter> ?????<!--请注意每添加一个appender，需要增加过滤器用于识别logger,同时需要增加DenyAllFilter，防止其他appender也插入日志--> ?????<!--<filter type="log4net.Filter.LoggerMatchFilter"> ???????<loggerToMatch value="OpenApiLog" /> ?????</filter> ?????<filter type="log4net.Filter.DenyAllFilter" />--> ?????<filter type="log4net.Filter.LoggerMatchFilter"> ???????<loggerToMatch value="gops" /> ?????</filter> ?????<filter type="log4net.Filter.DenyAllFilter" /> ???</appender> ???<root> ?????<!--(高) OFF > FATAL > ERROR > WARN > INFO > DEBUG > ALL (低) --> ?????<level value="all" /> ?????<appender-ref ref="AdoNetAppender"/> ?????<!--<appender-ref ref="OpenApiAppender"/>--> ???</root> ?</log4net></configuration>Log4Net基础配置
原文地址：https://www.cnblogs.com/Luis-Gong/p/9473686.html