为什么我不能使用 nlog 将日志跟踪写入文件？

Question

我开始学习如何在 .net 核心 web API 应用程序中配置 nlog。并阅读了一些教程，并尝试从 github

的官方教程中实现实现

1) 创建nlog.confiq xml 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="Trace" 
  internalLogFile="D:/Projects/appstore2/AppStore/AppStore.DataAccessLayer/Logs/InnerLog.txt">

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

<variable name="PathToFile" value="D:/Projects/appstore2/AppStore/AppStore.DataAccessLayer/Logs"/>

<!-- define various log targets -->
<targets async="true">    
  <!-- write logs to file -->
  <target name="logfile" xsi:type="File" fileName="D:/Projects/appstore2/AppStore/AppStore.DataAccessLayer/Logs/${shortdate}_log.txt" layout="${longdate} ${level:uppercase=true} ${message}"/>

</targets>

<rules>
  <logger name="*" minlevel="Trace" writeTo="logfile" final="true"/>
</rules>

2) 配置我的 Programm.cs

public class Program
{
    public static void Main(string[] args)
    {
        var logger = NLog.Web.NLogBuilder.ConfigureNLog("nlog.config").GetCurrentClassLogger();

        try
        {
            logger.Debug("init main");
            CreateWebHostBuilder(args).Build().Run();
        }
        catch (Exception ex)
        {
            //NLog: catch setup errors
            logger.Fatal(ex, "Stopped program because of exception");
            throw;
        }
        finally
        {
            // Ensure to flush and stop internal timers/threads before application-exit (Avoid segmentation fault on Linux)
            NLog.LogManager.Shutdown();
        }
    }

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

3) 更改 json 文件并添加下一个代码：

"Logging": {
    "LogLevel": {
        "Default": "Trace",
        "Microsoft": "Information"
    }
}

4) 之后，我在控制器中创建私有字段 class

 private readonly ILogger<UserController> _logger;

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

并在 try/catch

中使用此记录器

 catch (Exception ex)
    {
        _logger.LogWarning(ex, "LOG WARNING HELLOOOO");
        _logger.LogTrace(ex, "LOG TRACE HELLOOOO");
        return StatusCode(500, ex.Message);
    }

但是当我创建错误情况时，我的文件中没有 LogTrace 信息

2019-08-20 19:52:21.9065 INFO Executing action method AppStore.Web.Controllers.UserController.AddAsync (AppStore.Web) - Validation state: Valid Blockquote

2019-08-20 19:52:22.2795 WARN LOG WARNING HELLOOOO

2019-08-20 19:52:22.2817 INFO Executed action method AppStore.Web.Controllers.UserController.AddAsync (AppStore.Web), returned result Microsoft.AspNetCore.Mvc.NotFoundObjectResult in 373.2219ms.

为什么看不到trace信息，是我配置有问题还是需要做其他实现。我测试了 log -error、info、warn、fatal 但只有 trace 没有保存在我的文件中。

Answer 1

如Configure appsettings.json表示：

The Logging configuration specified in appsettings.json overrides any call to SetMinimumLevel. So either remove "Default": or adjust it correctly to your needs.

{
    "Logging": {
        "LogLevel": {
            "Default": "Trace",
            "Microsoft": "Information"
        }
    }
}

Remember to also update any environment specific configuration to avoid any surprises. Ex appsettings.Development.json

您需要更改 appsettings.json 和 appsettings.Development.json 中的 Logging 部分。

对于appsettings.Development.json，您可以勾选appsettings.json或打开项目文件夹进行查找和编辑。

为什么我不能使用 nlog 将日志跟踪写入文件？

Why I can't write to log trace to file using nlog?

c#

logging

nlog

asp.net-web-api

asp.net-core