Log to Event Viewer in an ASP .Net Core 2.1 Web API

问题

I'm trying to log to the Event Viewer in an ASP .Net Core 2.1 Web API, hosted on Windows Server 2016 Standard.

I've got this in my controller:

private readonly ILogger<MyController> _logger;
private readonly MyContext _context;

public TestController(MyContext context, ILogger<MyController> logger)
{
    _context = context;
    _logger = logger;
}

But I think I'm doing something wrong in my CreateWebHostBuilder() method in Program.cs because it's not working:

I had this:

public static IWebHostBuilder CreateWebHostBuilder(string[] args) =>
        WebHost.CreateDefaultBuilder(args)
            .UseStartup<Startup>();

and I modified it to this:

public static IWebHostBuilder CreateWebHostBuilder(string[] args) =>
            WebHost.CreateDefaultBuilder(args)
                .UseStartup<Startup>()
            .ConfigureLogging((hostingContext, logging) =>
            {
                logging.AddConfiguration(hostingContext.Configuration.GetSection("Logging"));
                logging.AddEventSourceLogger();
            });

But I must be doing something wrong... Any ideas? I read here that apparently EVent Viewer logging is now baked into .Net Core 2.1 Write to EventLog in .Net Core

回答1:

Ok, I had to add Microsoft.Extensions.Logging.EventLog to the project (from Nuget).

Then, in Startup.cs:

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

回答2:

For anyone who stumbles upon this using .NET Core 2.2, the Event Log logger (from Microsoft.Extensions.Logging.EventLog) should now be added in the Program.cs:

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

public static IWebHostBuilder CreateWebHostBuilder(string[] args) =>
    WebHost.CreateDefaultBuilder(args)
        .ConfigureLogging((context, logging) =>
        {
            logging.AddEventLog();
        })
        .UseStartup<Startup>();

This is noted at the bottom of the .NET Core Logging docs.

来源：https://stackoverflow.com/questions/52310072/log-to-event-viewer-in-an-asp-net-core-2-1-web-api