记录日志(Log4Net)

---

一：Log4net的简单示例

1、新建控制台应用程序，右键属性，把其框架.NET Framework4 Client Profile 修改为.NET Framework4，此时项目中将会自动添加一个App.config文件

　　内容如下：　　

<?xml version="1.0"?>
<configuration>
<startup><supportedRuntime version="v4.0" sku=".NETFramework,Version=v4.0"/></startup>
</configuration>

2、引用第三方类库：log4net.dll

3、在App.config文件中进行如下配置：　　

<?xml version="1.0"?>
<configuration>
  <configSections>
    <section name="log4net" type="log4net.Config.Log4NetConfigurationSectionHandler, log4net"/>
  </configSections>
  <log4net>
    <!-- Define some output appenders -->
    <appender name="RollingLogFileAppender" type="log4net.Appender.RollingFileAppender">
      <file value="test.txt"/>
      <appendToFile value="true"/>
      <!--可存的日志文件的个数-->
      <maxSizeRollBackups value=""/>
      <!--每个日志文件的大小-->
      <maximumFileSize value="1024KB"/>
      <rollingStyle value="Size"/>
      <staticLogFileName value="true"/>
      <layout type="log4net.Layout.PatternLayout">
        <!--日志格式-->
        <conversionPattern value="%date [%thread] %-5level %logger - %message%newline"/>
      </layout>
    </appender>
    <root>
      <!--日志记录的级别：None-Fatal(崩溃级别)-ERROR(错误级别)-WARN(警告级别)-DEBUG(bug级别)-INFO(信息级别)-ALL(所有)-->
      <level value="DEBUG"/>
      <appender-ref ref="RollingLogFileAppender"/>
    </root>
  </log4net>
  <startup>
    <supportedRuntime version="v4.0" sku=".NETFramework,Version=v4.0"/>
  </startup>
</configuration>

4、代码如下：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using log4net;

namespace Log4Demo
{
    class Program
    {
        static void Main(string[] args)
        {
            log4net.Config.XmlConfigurator.Configure();//初始化配置
            ILog log = log4net.LogManager.GetLogger("demo");//获取记录日志的实例

            log.Debug("这是调试信息！");
        }
    }
}

5、日志文件就会写入项目根目录bin\Debug下的一个test.txt文件中。

二、在项目中的应用

1、有一个MVC项目，首先引用log4net.dll类库，然后在web.config中配置，添加标识中的内容：　　

<configuration>
  <!--新加配置内容-->
  <configSections>
    <section name="log4net" type="log4net.Config.Log4NetConfigurationSectionHandler, log4net"/>
  </configSections>
  <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="&quot;Logs_&quot;yyyyMMdd&quot;.txt&quot;" />
      <param name="StaticLogFileName" value="false" />
      <layout type="log4net.Layout.PatternLayout,log4net">
        <param name="ConversionPattern" value="%d [%t] %-5p %c - %m%n" />
        <param name="Header" value="
----------------------header--------------------------
" />
        <param name="Footer" value="
----------------------footer--------------------------
" />
      </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>
  <connectionStrings>
    <add name="ApplicationServices"
         connectionString="data source=.\SQLEXPRESS;Integrated Security=SSPI;AttachDBFilename=|DataDirectory|aspnetdb.mdf;User Instance=true"
         providerName="System.Data.SqlClient" />
  </connectionStrings>
  <!--新加配置内容结束-->
  <appSettings>
    <add key="ClientValidationEnabled" value="true"/>
    <add key="UnobtrusiveJavaScriptEnabled" value="true"/>
  </appSettings>

  <system.web>
    <compilation debug="true" targetFramework="4.0">
      <assemblies>
        <add assembly="System.Web.Abstractions, Version=4.0.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35" />
        <add assembly="System.Web.Helpers, Version=1.0.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35" />
        <add assembly="System.Web.Routing, Version=4.0.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35" />
        <add assembly="System.Web.Mvc, Version=3.0.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35" />
        <add assembly="System.Web.WebPages, Version=1.0.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35" />
      </assemblies>
    </compilation>

2、然后在Global.asax.cs问价中，初始化我们的配置：　　

   protected void Application_Start()
        {
            AreaRegistration.RegisterAllAreas();

            RegisterGlobalFilters(GlobalFilters.Filters);
            RegisterRoutes(RouteTable.Routes);

            log4net.Config.XmlConfigurator.Configure();//初始化配置
        }

3、在HomeController中添加代码如下：　　

  public ActionResult Index()
        {
            ViewBag.Message = "欢迎使用 ASP.NET MVC!";
            ViewData["count"] = GetCount.TotalCount();

            try
            {
                int i = ;
                int y =  / i;
            }
            catch (Exception exception)
            {
                ILog log = LogManager.GetLogger("demo");
                log.Error("计算：" + exception.ToString());
            }
            return View();
        }

4、运行，自动生成日志文件。查看方式：右键，App_Data文件，在Windows资源管理器中打开，就会看到生成的日志文件。