public class HomeController : Controller
 {
  private readonly ILogger<HomeController> _logger;

  public HomeController(ILogger<HomeController> logger)
  {
   _logger = logger;
  }
  public IActionResult Index()
  {
   _logger.LogInformation("你访问了首页");
   _logger.LogWarning("警告信息");
   _logger.LogError("错误信息");
   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();
  }
 }

Install-Package System.Text.Encoding.CodePages -Pre

  public void Configure(IApplicationBuilder app, IHostingEnvironment env, ILoggerFactory loggerFactory)
  {
   Encoding.RegisterProvider(CodePagesEncodingProvider.Instance);

Install-Package NLog.Extensions.Logging -Pre

<"1.0" encoding="utf-8" "http://www.nlog-project.org/schemas/NLog.xsd"
  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  autoReload="true"
  internalLogLevel="Warn"
  internalLogFile="internal-nlog.txt">

 <!-- define various log targets -->
 <targets>
 <!-- write logs to file -->
 <target xsi:type="File" name="allfile" fileName="nlog-all-${shortdate}.log"
     layout="${longdate}|${logger}|${uppercase:${level}}|${message} ${exception}" />


 <target xsi:type="File" name="ownFile-web" fileName="nlog-own-${shortdate}.log"
    layout="${longdate}|${logger}|${uppercase:${level}}| ${message} ${exception}" />

 <target xsi:type="Null" name="blackhole" />
 </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>

  public void Configure(IApplicationBuilder app, IHostingEnvironment env, ILoggerFactory loggerFactory)
  {
   loggerFactory.AddNLog();//添加NLog

"publishOptions": {
 "include": [
  "wwwroot",
  "Views",
  "appsettings.json",
  "web.config",
  "nlog.config"//加上nlog配置文件
 ]
 },