【转】NetCore使用Nlog记录日志

原文地址：https://www.cnblogs.com/wtujvk/p/13222233.html

（说明：博主编写Demo自学项目，部分图片来源于自己Demo过程的截图）

当前环境： win10+vs2019+netcore3.1

添加Nuget包引用：NLog.Web.AspNetCore

1：新建ASP.NET Core Web应用程序，选择了带模型视图控制器的：

 

 

 添加Nuget包引用：NLog.Web.AspNetCore 

 

 2. 添加 nlog.config配置文件 或者安装包 nlog.config

  文件内容：

<?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="Info"
      internalLogFile="c:\temp\internal-nlog.txt">
    <!-- enable asp.net core layout renderers -->
    <extensions>
        <add assembly="NLog.Web.AspNetCore"/>
    </extensions>

    <!-- the targets to write to -->
    <targets>
        <!-- write logs to file  -->
        <target xsi:type="File" name="allfile" fileName="logs\nlog-all-${shortdate}.log"
                layout="${longdate}|${event-properties:item=EventId_Id}|${uppercase:${level}}|${logger}|${message} ${exception:format=tostring}" />

        <!-- another file log, only own logs. Uses some ASP.NET core renderers -->
        <target xsi:type="File" name="ownFile-web" fileName="logs\nlog-own-${shortdate}.log"
                layout="${longdate}|${event-properties:item=EventId_Id}|${uppercase:${level}}|${logger}|${message} ${exception:format=tostring}
|url: ${aspnet-request-url}|action: ${aspnet-mvc-action}" />
    </targets>

    <!-- rules to map from logger name to target -->
    <rules>
        <!--All logs, including from Microsoft-->
        <logger name="*" minlevel="Trace" writeTo="allfile" />

        <!--Skip non-critical Microsoft logs and so log only own logs-->
        <logger name="Microsoft.*" maxlevel="Info" final="true" />
        <!-- BlackHole without writeTo -->
        <logger name="*" minlevel="Trace" writeTo="ownFile-web" />
    </rules>
</nlog>

autoReload自动再配置(Automatic reconfiguration)

一旦启动程序，这时候NLog.config文件被读取后，知道程序再启动都不会再读取配置文件了。假如我们不想停掉程序，比如说服务器哪能说停就停哈。这就用上这个配置了，这个配置功能是，一旦你对配置文件修改，程序将会重新读取配置文件，也就是自动再配置。

日志排错(Troubleshooting logging) 

   <nlog throwExceptions="true" />   
    <nlog internalLogFile=" c:\log\nlog.txt " />- 设置internalLogFile属性可以让NLog把内部的调试和异常信息都写入指定文件里。
    <nlog internalLogLevel="Trace|Debug|Info|Warn|Error|Fatal" /> - 决定内部日志的级别，级别越高，输出的日志信息越简洁。internalLogLevel="Off" 关闭
    <nlog internalLogToConsole="false|true" /> - 是否把内部日志输出到标准控制台。
    <nlog internalLogToConsoleError="false|true" /> - 是否把内部日志输出到标准错误控制台 (stderr)。

设置throwExceptions属性为“true”可以让NLog不再阻挡这类异常，而是把它们抛给调用者。在部署是这样做可以帮我们快速定位问题。一旦应用程序已经正确配置了，我们建议把throwExceptions的值设为“false”，这样由于日志引发的问题不至于导致应用程序的崩溃。

实战配置：

<nlog xmlns="http://www.nlog-project.org/schemas/NLog.xsd" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
      autoReload="true"      internalLogLevel="Off"      throwExceptions="false">

如果nlog.config在其他位置配置，要设置始终复制或者有新的复制

其他补充：csv配置

 

<?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" 
      throwExceptions="false" internalLogLevel="Off" internalLogFile="NlogRecords.log">
  <!--Nlog内部日志记录为Off关闭。除非纠错，不可以设为Trace否则速度很慢，起码Debug以上-->
  <extensions>
    <add assembly="NLog.Web.AspNetCore" />
  </extensions>
  <targets>
    <!--通过数据库记录日志 配置
    dbProvider请选择mysql或是sqlserver，同时注意连接字符串,需要安装对应的sql数据提供程序
    MYSQL:
    dbProvider="MySql.Data.MySqlClient.MySqlConnection, MySql.Data"
    connectionString="server=localhost;database=BaseMIS;user=root;password=123456"
    MSSQL:
    dbProvider="Microsoft.Data.SqlClient.SqlConnection, Microsoft.Data.SqlClient"
    connectionString="Server=127.0.0.1;Database=BaseMIS;User ID=sa;Password=123456"
    -->
    <target name="log_database" xsi:type="Database" dbProvider="Microsoft.Data.SqlClient.SqlConnection, Microsoft.Data.SqlClient" 
     connectionString="Server=127.0.0.1;uid=sa;Pwd=pwd;Database=dbname;MultipleActiveResultSets=true;pooling=true;
       min pool size=5;max pool size=32767;connect timeout=20;Encrypt=True;TrustServerCertificate=True;">
      <commandText>
        INSERT INTO SysNLogRecords
        (LogDate,LogLevel,LogType,LogTitle,Logger,Message,MachineName,MachineIp,NetRequestMethod
        ,NetRequestUrl,NetUserIsauthenticated,NetUserAuthtype,NetUserIdentity,Exception)
        VALUES
        (@LogDate,@LogLevel,@LogType,@LogTitle,@Logger,@Message,@MachineName,@MachineIp,@NetRequestMethod
        ,@NetRequestUrl,@NetUserIsauthenticated,@NetUserAuthtype,@NetUserIdentity,@Exception);
      </commandText>
      <parameter name="@LogDate" layout="${date}" />
      <parameter name="@LogLevel" layout="${level}" />
      <parameter name="@LogType" layout="${event-properties:item=LogType}" />
      <parameter name="@LogTitle" layout="${event-properties:item=LogTitle}" />
      <parameter name="@Logger" layout="${logger}" />
      <parameter name="@Message" layout="${message}" />
      <parameter name="@MachineName" layout="${machinename}" />
      <parameter name="@MachineIp" layout="${aspnet-request-ip}" />
      <parameter name="@NetRequestMethod" layout="${aspnet-request-method}" />
      <parameter name="@NetRequestUrl" layout="${aspnet-request-url}" />
      <parameter name="@NetUserIsauthenticated" layout="${aspnet-user-isauthenticated}" />
      <parameter name="@NetUserAuthtype" layout="${aspnet-user-authtype}" />
      <parameter name="@NetUserIdentity" layout="${aspnet-user-identity}" />
      <parameter name="@Exception" layout="${exception:tostring}" />
    </target>
    <target xsi:type="File" name="log_file" fileName="${basedir}/App_Data/nlog/${date:format=yyyy-MM}/${level}-${shortdate}.csv" encoding="utf-8">
      <layout xsi:type="CSVLayout">
        <column name="date" layout="${date}" />
        <column name="LogTitle" layout="${event-properties:item=LogTitle}" />
        <column name="message" layout="${message}" />
        <column name="exception" layout="${exception:format=tostring}" />
        <column name="machinename" layout="${machinename}" />
        <column name="appdomain" layout="${appdomain}" />
        <column name="assembly-version" layout=" ${assembly-version}" />
        <column name="basedir" layout="${basedir}" />
        <column name="callsite" layout="${callsite}" />
        <column name="counter" layout="${counter}" />
        <column name="nlogdir" layout="${nlogdir}" />
        <column name="processid" layout="${processid}" />
        <column name="processname" layout="${processname}" />
        <column name="specialfolder" layout="${specialfolder}" />
        <column name="stacktrace" layout="${stacktrace}" />
        <column name="longdate" layout="${longdate}" />
        <column name="event-properties" layout="${event-properties:item=EventId_Id}" />
        <column name="uppercase" layout="${uppercase:${level}}" />
        <column name="logger" layout="${logger}" />
        <column name="url" layout="${aspnet-request-url}" />
        <column name="action" layout="${aspnet-mvc-action}" />
      </layout>
    </target>
  </targets>
  <rules>
    <!--跳过所有级别的Microsoft组件的日志记录-->
    <logger name="Microsoft.*" final="true" />
    <!-- BlackHole without writeTo -->
    <!--只通过数据库记录日志，如果给了name名字，cs里用日志记录的时候，取logger需要把name当做参数-->
    <logger name="logdb" writeTo="log_database" />
    <logger name="logfile" writeTo="log_file" />
  </rules>
</nlog>

 

3. 在CreateHostBuilder 中添加使用Nlog ( ConfigureLogging)

using Microsoft.AspNetCore.Hosting;
using Microsoft.Extensions.Hosting;
using Microsoft.Extensions.Logging;
using NLog.Web;

namespace WebApplication2
{
    public class Program
    {
        public static void Main(string[] args)
        {
            CreateHostBuilder(args).Build().Run();
        }

        public static IHostBuilder CreateHostBuilder(string[] args) =>
            Host.CreateDefaultBuilder(args)
                .ConfigureWebHostDefaults(webBuilder =>
                {
                    webBuilder.UseStartup<Startup>();
                })
                .ConfigureLogging(
                    logging =>
                    {
                        // 清除系统默认的日志
                        //logging.ClearProviders();
                        logging.SetMinimumLevel(LogLevel.Trace);
                    }).UseNLog();
    }
}

4. 调用

using Microsoft.AspNetCore.Mvc;
using Microsoft.Extensions.Logging;
using System.Diagnostics;
using WebApplication2.Models;
namespace WebApplication2.Controllers
{
    public class HomeController : Controller
    {
        //创建好的项目自带的
        private readonly ILogger<HomeController> _logger;

        public HomeController(ILogger<HomeController> logger)
        {
            //创建好的项目自带的
            _logger = logger;
            //自己添加的部分
            _logger.LogDebug(1, "NLog injected into HomeController");
        }

        public IActionResult Index()
        {
            //自己添加的部分
            _logger.LogInformation("Hello, this is the index!");
            return View();
        }
    }
}

6. 效果

在bin\Debug\netcoreapp3.1 目录下生成了logs文件夹

 配置信息处internalLogFile如果配置成（internalLogFile="internal-nlog-ttttt.txt"）

生成的位置在项目的根目录