.net 5.0 下记录日志以及日志的配置

1.我们先开始准备一个日志的Helper

2.然后在指定目录下添加配置文件 .XML

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

namespace AnnualBill.Logger
{
    public class LoggerHelper
    {
        #region Fields
        private static readonly ILog logger;
        #endregion

        #region Constructors
        static LoggerHelper()
        {
            if (logger == null)
            {
                var repository = LogManager.CreateRepository("MixdoRepository");
                //log4net从log4net.config文件中读取配置信息
                var log4netConfig = new FileInfo("App_Data/log4net.config.xml");
                XmlConfigurator.Configure(repository, log4netConfig);
                logger = LogManager.GetLogger(repository.Name, "InfoLogger");
            }
        }
        #endregion

        #region Utilities
        /// <summary>
        /// 普通日志
        /// </summary>
        /// <param name="message"></param>
        /// <param name="exception"></param>
        public static void Info(string message, Exception exception = null)
        {
            if (exception == null)
                logger.Info(message);
            else
                logger.Info(message, exception);
        }

        /// <summary>
        /// 告警日志
        /// </summary>
        /// <param name="message"></param>
        /// <param name="exception"></param>
        public static void Warn(string message, Exception exception = null)
        {

            if (exception == null)
                logger.Warn(message);
            else
                logger.Warn(message, exception);
        }

        /// <summary>
        /// 错误日志
        /// </summary>
        /// <param name="message"></param>
        /// <param name="exception"></param>
        public static void Error(string message, Exception exception = null)
        {

            if (exception == null)
                logger.Error(message);
            else
                logger.Error(message, exception);
        }

        #endregion
    }
}

<?xml version="1.0" encoding="utf-8"?>
<log4net>
    <!-- Define some output appenders -->
    <appender name="rollingAppender" type="log4net.Appender.RollingFileAppender">
        <file value="log.txt" />
        <!--追加日志内容-->
        <appendToFile value="true" />

        <!--防止多线程时不能写Log-->
        <lockingModel type="log4net.Appender.FileAppender+MinimalLock" />

        <!--可以为:Once|Size|Date|Composite-->
        <!--Composite为Size和Date的组合-->
        <rollingStyle value="Composite" />

        <!--当备份文件时,为文件名加的后缀-->
        <datePattern value="yyyyMMdd.TXT" />

        <!--日志最大个数,都是最新的-->
        <!--rollingStyle节点为Size时,只能有value个日志-->
        <!--rollingStyle节点为Composite时,每天有value个日志-->
        <maxSizeRollBackups value="20" />

        <!--可用的单位:KB|MB|GB-->
        <maximumFileSize value="3MB" />

        <!--置为true,当前最新日志文件名永远为file节中的名字-->
        <staticLogFileName value="true" />

        <!--输出级别在INFO和ERROR之间的日志-->
        <filter type="log4net.Filter.LevelRangeFilter">
            <param name="LevelMin" value="ALL" />
            <param name="LevelMax" value="FATAL" />
        </filter>
        <layout type="log4net.Layout.PatternLayout">
            <conversionPattern value="%date [%thread] %-5level %logger - %message%newline"/>
        </layout>
    </appender>
    <root>
        <priority value="ALL"/>
        <level value="ALL"/>
        <appender-ref ref="rollingAppender" />
    </root>
</log4net>