ASP.net：如何从CreateHostBuilder（）中登录？

debugcn 发表于 Dev

尿

我有一个ASP.net Core 3.1 Web应用程序。在Program.cs该类中，我实现了CreateHostBuilder()类似于以下内容的静态方法：

public static IHostBuilder CreateHostBuilder(string[] args) =>
    Host
        .CreateDefaultBuilder(args)
        .ConfigureAppConfiguration((context, config) =>
        {
            try 
            {
                // do some configuration work that might fail
            }
            catch (Exception ex)
            {
                // how can I write to a log from here?
            }
        })
        .ConfigureWebHostDefaults(webBuilder =>
        {
            webBuilder.UseStartup<Startup>();
        });
}

如果在配置应用程序时引发异常，如何ILogger在捕获时使用an记录它？

埃德

将记录器放置在Main方法之外，以使其可从CreateHostBuilder访问

using Microsoft.AspNetCore.Hosting;
using Microsoft.Extensions.Hosting;
using NLog.Common;
using System;
using System.IO;

namespace WebApplication1
{
    public class Program
    {
        // Place your logger outside Main to make it accessible from CreateHostBuilder
        private static NLog.Logger logger;

        public static void Main(string[] args)
        {
            // Manually setup your desired logger.
            // I've used NLog for demonstration purposes but you can use your own preferred logger.
            var today = DateTime.Today.ToString("yyyy-MM-dd");
            var binDirectory = GetBinDirectory<Program>();
            var nLogInternalFullPath = Path.Combine(binDirectory, "NLog", $"{today}-internal.log");

            InternalLogger.LogFile = nLogInternalFullPath;

            // Assign logger. Make sure you have the file NLog.config
            // https://github.com/NLog/NLog/wiki/File-target
            logger = NLog.LogManager.LoadConfiguration("NLog.config").GetCurrentClassLogger();

            CreateHostBuilder(args).Build().Run();
        }

        public static IHostBuilder CreateHostBuilder(string[] args) =>
            Host.CreateDefaultBuilder(args)
                .ConfigureAppConfiguration((context, config) =>
                {
                    try
                    {
                        // do some configuration work that might fail
                    }
                    catch (Exception ex)
                    {
                        // Log errors
                        logger.Error(ex, "Unhandled error in ConfigureAppConfiguration.");
                    }
                })
                .ConfigureWebHostDefaults(webBuilder =>
                {
                    webBuilder.UseStartup<Startup>();
                });

        public static string GetBinDirectory<T>()
        {
            return Path.GetDirectoryName(typeof(T).Assembly.Location);
        }
    }
}

本文收集自互联网，转载请注明来源。

如有侵权，请联系[email protected] 删除。