Log4net

直接上代码

1   nuget  下载 log4net。这个不多说了，大家都会

2   web.config （下面是两套配置，我的项目webapi和mvc网站记录的文件夹不同）

web和webapi一起写的：

  <log4net>  
    <root>  
      <appender-ref ref="WebLog" />  
    </root>  
    <appender name="WebLog" type="log4net.Appender.RollingFileAppender,log4net">  
      <file value="Log/" />  
      <appendToFile value="true" />  
      <rollingStyle value="Date" />  
      <datePattern value="yyyy-MM-dd_HH&quot;.txt&quot;" />  
      <maxSizeToRollBackups value="10" />  
      <maximumFileSize value="5MB" />  
      <staticLogFileName value="false" />  
      <layout type="log4net.Layout.PatternLayout,log4net">  
        <conversionPattern value="%d - %-5level - %c - %m%n" />  
      </layout>  
      <lockingModel type="log4net.Appender.FileAppender+MinimalLock" />  
    </appender>  
  </log4net> 

web和webapi分开写的：

<configuration>  
 <!-- 这句很重要 -->
<section name="log4net" type="log4net.Config.Log4NetConfigurationSectionHandler,log4net" />

<log4net>
    <root>
      <appender-ref ref="ApiLog" />
      <appender-ref ref="WebLog" />
    </root>
    <appender name="ApiLog" type="log4net.Appender.RollingFileAppender">
      <file value="LogApi" />
      <appendToFile value="true" />
      <rollingStyle value="Date" />
      <datePattern value="yyyy-MM-dd&quot;.log&quot;" />
      <maxSizeToRollBackups value="10" />
      <maximumFileSize value="5MB" />
      <staticLogFileName value="false" />
      <filter type="log4net.Filter.LoggerMatchFilter">
        <loggerToMatch value="ApiLog" />
      </filter>
      <filter type="log4net.Filter.DenyAllFilter" />
      <layout type="log4net.Layout.PatternLayout,log4net">
        <conversionPattern value="%d - %-5level - %c - %m%n" />
      </layout>
      <lockingModel type="log4net.Appender.FileAppender+MinimalLock" />
    </appender>


    <appender name="WebLog" type="log4net.Appender.RollingFileAppender">
      <file value="LogWeb" />
      <appendToFile value="true" />
      <rollingStyle value="Date" />
      <datePattern value="yyyy-MM-dd&quot;.log&quot;" />
      <maxSizeToRollBackups value="10" />
      <maximumFileSize value="5MB" />
      <staticLogFileName value="false" />
      <filter type="log4net.Filter.LoggerMatchFilter">
        <loggerToMatch value="WebLog" />
      </filter>
      <filter type="log4net.Filter.DenyAllFilter" />
      <layout type="log4net.Layout.PatternLayout,log4net">
        <conversionPattern value="%d - %-5level - %c - %m%n" />
      </layout>
      <lockingModel type="log4net.Appender.FileAppender+MinimalLock" />
    </appender>
  </log4net>

</configuration>

3   记录日志  在 Global.asax

void Application_Start(object sender, EventArgs e)
        {
            log4net.Config.XmlConfigurator.Configure();
        //log4net.Config.XmlConfigurator.Configure(new FileInfo(Server.MapPath("~/Web.config")));
        }

void Application_Error(object sender, EventArgs e)
        {
            Exception ex = Server.GetLastError().GetBaseException();
            string msg = "
" + "StackTrace:
" + ex.StackTrace 
                         + "

" + "Message:
" 
                         + ex.Message + "



";

            //根据不同的Log对象，执行记录
            //记录api的异常
            log4net.ILog log = log4net.LogManager.GetLogger("APILog");
            //记录web的异常
            log4net.ILog log = log4net.LogManager.GetLogger("WebLog"); 

            log4net.Config.XmlConfigurator.Configure(); 
            log.Info(msg); 
            Server.ClearError(); 
            Response.Redirect("~/ErrorManager/ErrorPage"); 
         }

PS ：发布的时候，一定要到 bin目录下 找到 log4net.xml这个文件一起拷贝到站点！