ASP.NET Core 添加NLog日志支持(VS2015update3&VS2017)

创建一个新的ASP.NET Core项目

添加项目依赖

• NLog.Web.AspNetCore

在项目目录下添加nlog.config文件

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

   <!-- 加载ASP.NET Core插件 -->
   <extensions>
     <add assembly="NLog.Web.AspNetCore"/>
   </extensions>

   <!-- 输出目的地 -->
   <targets>
      <!-- 输出到文件,这个文件记录所有日志 -->
      <target xsi:type="File" name="allfile" fileName="c:\temp\nlog-all-${shortdate}.log"
                  layout="${longdate}|${event-properties:item=EventId.Id}|${logger}|${uppercase:${level}}|${message} ${exception}" />

    <!-- 另外一个日志记录文件,户口也跳过Microsoft开头相关日志信息 -->
      <target xsi:type="File" name="ownFile-web" fileName="c:\temp\nlog-own-${shortdate}.log"
              layout="${longdate}|${event-properties:item=EventId.Id}|${logger}|${uppercase:${level}}|  ${message} ${exception}|url: ${aspnet-request-url}|action: ${aspnet-mvc-action}" />

      <!-- write to the void aka just remove -->
     <target xsi:type="Null" name="blackhole" />
   </targets>

   <!-- 写入目的地的规则 -->
   <rules>
     <!--全部记录,包括Microsoft开头的相关日志信息-->
     <logger name="*" minlevel="Trace" writeTo="allfile" />

     <!--跳过Microsoft开头的相关日志信息-->
     <logger name="Microsoft.*" minlevel="Trace" writeTo="blackhole" final="true" />
     <logger name="*" minlevel="Trace" writeTo="ownFile-web" />
   </rules>
 </nlog>

将nlog.config复制到bin文件夹

在startup.cs文件中添加(红字)

 using NLog.Extensions.Logging;
 using NLog.Web;

 public Startup(IHostingEnvironment env)
 {
     env.ConfigureNLog("nlog.config");
 }

 public void ConfigureServices(IServiceCollection Services)
 {
     //call this in case you need aspnet-user-authtype/aspnet-user-identity
     services.AddSingleton<IHttpContextAccessor, HttpContextAccessor>();
 }

 // This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
 public void Configure(IApplicationBuilder app, IHostingEnvironment env, ILoggerFactory loggerFactory)
 {

     //add NLog to ASP.NET Core
     loggerFactory.AddNLog();

     //add NLog.Web
     app.AddNLogWeb();

    //note: remove the old loggerFactory, like loggerFactory.AddConsole and  loggerFactory.AddDebug

记录日志

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

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

         public IActionResult Index()
         {
             _logger.LogInformation("Index page says hello");
             return View();
         }

运行ASP.NET Core网站,会生成两个文件

nlog-own-2017-04-28.log和nlog-all-2017-04-28.log