一行代码在 .NET Core 中快速使用 log4net

1. .NET Core 控制台程序中使用

第一步：添加引用

Install-Package log4net

第二步：将附件?LogHelper.cs 和 log4net.config 两个文件加入到项目中

第三步：在Main中使用 LogHelper 类来记录日志

        public static void Main(string[] args)
        {
            LogHelper.Configure(); //使用前先配置

            LogHelper.Info("NETCorelog4net log");
            LogHelper.Info("test log");
            LogHelper.Error("error");
            LogHelper.Info("linezero");
            Console.ReadKey();
        }

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2.?ASP.NET Core 中使用

第一步：添加引用

Install-Package log4net

第二步：将附件?LogHelper.cs 和 log4net.config 两个文件加入到项目中

第三步：在Startup 构造函数中初始化

    public class Startup
    {
        public Startup()
        {
            LogHelper.Configure(); //使用前先配置
        }

第三步：在HomeController 中使用 LogHelper 类来记录日志

        public IActionResult Index()
        {
            LogHelper.Info("index view");
            LogHelper.Error("Controller Error");
            return View();
        }

?

附件

日志类简单封装：LogHelper.cs

    using log4net;
    using log4net.Config;
    using log4net.Repository;
    using System.IO;

    public class LogHelper
    {
        private static ILoggerRepository repository { get; set; }
        private static ILog _log;
        private static ILog log {
            get
            {
                if (_log == null)
                {
                    Configure();
                }
                return _log;
            }
        }

        public static void Configure(string repositoryName = "NETCoreRepository", string configFile = "log4net.config")
        {
            repository = LogManager.CreateRepository(repositoryName);
            XmlConfigurator.Configure(repository, new FileInfo(configFile));
            _log = LogManager.GetLogger(repositoryName, "");
        }

        public static void Info(string msg)
        {
            log.Info(msg);
        }

        public static void Warn(string msg)
        {
            log.Warn(msg);
        }

        public static void Error(string msg)
        {
            log.Error(msg);
        }
    }

log4net 配置文件：log4net.config?

<?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="logfile/" />
      <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>