1、根目录新建nlog.config配置文件

<?xml version="1.0"?>
<nlog xmlns="http://www.nlog-project.org/schemas/NLog.xsd"
      xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
      autoReload="true"
      internalLogLevel="Warn"
      internalLogFile="${basedir}\logs\internal-nlog.txt">

  <extensions>
    <add assembly="NLog.Web.AspNetCore"/>
  </extensions>

  <targets>
    <target name="allfile" xsi:type="File"
            fileName="${basedir}\logs\GDStationaryNetCore\${shortdate}.log"
            encoding="utf-8"
            layout="[${longdate}][${machinename}][${level}] ${message} ${exception}" />
  </targets>
  <rules>
    <!--All logs, including from Microsoft-->
    <logger name="*" minlevel="Trace" writeTo="allfile" />

    <!--Skip Microsoft logs and so log only own logs-->
    <logger name="Microsoft.*" minlevel="Trace" writeTo="blackhole" final="true" />
    <logger name="*" minlevel="Trace" writeTo="ownFile-web" />
  </rules>
</nlog>

2、添加NLog包

Install-Package NLog.Web.AspNetCore

3、Configure配置

public void Configure(IApplicationBuilder app, IHostingEnvironment env, ILoggerFactory loggerFactory)
        {
            if (env.IsDevelopment())
            {
                app.UseDeveloperExceptionPage();
            }

            //
            env.ConfigureNLog("nlog.config");
            //安装System.Text.Encoding.CodePages
            Encoding.RegisterProvider(CodePagesEncodingProvider.Instance);
            //add NLog to ASP.NET Core
            loggerFactory.AddNLog();
            //add NLog.Web
            // 修改为 CreateWebHostBuilder(args).UseNLog().Build().Run();
            //app.AddNLogWeb();

            app.UseMvc();
        }

Main方法里配置使用

 public static void Main(string[] args)
        {
            CreateWebHostBuilder(args).UseNLog().Build().Run();
        }

4、使用

public class ValuesController : ControllerBase
    {
        private readonly ILogger<ValuesController> _logger;

        public ValuesController(ILogger<ValuesController> logger = null)
        {
            if (null != logger)
            {
                _logger = logger;
            }
        }

        // GET api/values
        [HttpGet]
        public ActionResult<IEnumerable<string>> Get()
        {
            _logger.LogInformation($"测试一条日志.");
            return new string[] { "value1", "value2" };
        }

    }

原文地址：https://www.cnblogs.com/zhouxiaoyun/p/10765427.html