ASP.NET Core 2.0使用Log4net实现记录日志功能

一、安装Log4net

1、使用Nuget包进行安装

在依赖项上面右键，选择“管理NuGet程序包”，如下图所示：

在浏览界面输入log4net，然后点击安装，如下图所示：

2、使用程序包管理器控制台进行安装

使用Install-Package Log4net命令进行安装，如下图所示：

二、配置log4net使用的配置文件

配置文件如下：

 <?xml version="1.0" encoding="utf-8" ?>
  <configuration>
    <!-- This section contains the log4net configuration settings -->
    <log4net>
      <appender name="ConsoleAppender" type="log4net.Appender.ConsoleAppender">
        <layout type="log4net.Layout.PatternLayout" value="%date [%thread] %-5level %logger - %message%newline" />
      </appender>

      <appender name="FileAppender" type="log4net.Appender.FileAppender">
      <file value="log-file.log" />
      <appendToFile value="true" />
      <layout type="log4net.Layout.PatternLayout">
        <conversionPattern value="%date [%thread] %-5level %logger [%property{NDC}] - %message%newline" />
      </layout>
    </appender>

    <appender name="RollingLogFileAppender" type="log4net.Appender.RollingFileAppender">
      <file value="D:\study\logfile/" />   //指定日志文件保存的目录
      <appendToFile value="true" />
      <rollingStyle value="Composite" />
      <staticLogFileName value="false" />
      <datePattern value="yyyyMMdd'.log'" />
      <maxSizeRollBackups value="10" />
      <maximumFileSize value="1MB" />
      <layout type="log4net.Layout.PatternLayout">
        <conversionPattern value="%date [%thread] %-5level %logger [%property{NDC}] - %message%newline" />
      </layout>
    </appender>

    <!-- Setup the root category, add the appenders and set the default level -->
    <root>
      <level value="ALL" />
      <appender-ref ref="ConsoleAppender" />
      <appender-ref ref="FileAppender" />
        <appender-ref ref="RollingLogFileAppender" />
      </root>

    </log4net>
  </configuration>

三、在Startup.cs类里面配置使用log4net

 public static ILoggerRepository repository { get; set; }
 public Startup(IConfiguration configuration)
 {
             Configuration = configuration;
             repository = LogManager.CreateRepository("NETCoreRepository");
             // 指定配置文件
             XmlConfigurator.Configure(repository, new FileInfo("log4net.config"));
 }

四、在控制器里面注入log4net

 using System;
 using System.Collections.Generic;
 using System.Diagnostics;
 using System.Linq;
 using System.Threading.Tasks;
 using log4net;
 using Microsoft.AspNetCore.Hosting;
 using Microsoft.AspNetCore.Mvc;
 using NetCoreLogDemo.Models;

 namespace NetCoreLogDemo.Controllers
 {
     public class HomeController : Controller
     {
         private ILog log;

         public HomeController(IHostingEnvironment hostingEnv)
         {
             this.log = LogManager.GetLogger(Startup.repository.Name, typeof(HomeController));
         }

         public IActionResult Index()
         {
             log.Error("测试日志");
             return View();
         }

         public IActionResult About()
         {
             ViewData["Message"] = "Your application description page.";

             return View();
         }

         public IActionResult Contact()
         {
             ViewData["Message"] = "Your contact page.";

             return View();
         }

         public IActionResult Error()
         {
             return View(new ErrorViewModel { RequestId = Activity.Current?.Id ?? HttpContext.TraceIdentifier });
         }
     }
 }

测试结果：