.Net Core 3.1学习之使用扩展log4net

Step1：引入包Microsoft.Extensions.Logging.Log4.AspNetCore

Step2：写log4net.config文件

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

<!--防止多线程时不能写Log,官方说线程非安全-->
<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>

Step3:在Program.cs里添加配置

public static IHostBuilder CreateHostBuilder(string[] args) =>
Host.CreateDefaultBuilder(args)
.ConfigureLogging((context,logginBuilder)=> {
　　logginBuilder.AddLog4Net();
})
.ConfigureWebHostDefaults(webBuilder =>
{
webBuilder.UseStartup<Startup>();
});

Step:4在controller里进行使用

public class WeatherForecastController : ControllerBase
{
private static readonly string[] Summaries = new[]
{
　　"Freezing", "Bracing", "Chilly", "Cool", "Mild", "Warm", "Balmy", "Hot", "Sweltering", "Scorching"
};

private readonly ILogger<WeatherForecastController> _logger;

public WeatherForecastController(ILogger<WeatherForecastController> logger)
{
　　_logger = logger;
}

[HttpGet]
public IEnumerable<WeatherForecast> Get()
{
　　this._logger.LogInformation("information test");
　　var rng = new Random();
　　return Enumerable.Range(1, 5).Select(index => new WeatherForecast
　　{
　　　　Date = DateTime.Now.AddDays(index),
　　　　TemperatureC = rng.Next(-20, 55),
　　　　Summary = Summaries[rng.Next(Summaries.Length)]
　　})
　　.ToArray();
}
}

原文：https://www.cnblogs.com/xingzhu-nan/p/12528171.html