<?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內部日志記錄為Off關閉。除非糾錯，不可以設為Trace否則速度很慢，起碼Debug以上-->
 <extensions>
 <add assembly="NLog.Web.AspNetCore" />
 </extensions>
 <targets>
 <!--通過數(shù)據(jù)庫記錄日志 配置
 dbProvider請選擇mysql或是sqlserver，同時注意連接字符串,需要安裝對應的sql數(shù)據(jù)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"
 connectionString="Server=127.0.0.1;Database=BaseMIS;User ID=sa;Password=123456"
 -->
 <target name="log_database" xsi:type="Database" dbProvider="MySql.Data.MySqlClient.MySqlConnection, MySql.Data"
  connectionString="server=192.168.137.10;database=TestNLog;user=root;password=mysql@local">
 <commandText>
 INSERT INTO TblLogrecords 
 (LogDate,LogLevel,LogType,Logger,Message,MachineName,MachineIp,NetRequestMethod
 ,NetRequestUrl,NetUserIsauthenticated,NetUserAuthtype,NetUserIdentity,Exception)
 VALUES
 (@LogDate,@LogLevel,@LogType,@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="${event-properties:item=LogType}" />
 <parameter name="@Logger" layout="${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="${exception:tostring}" />
 </target>
 <target name="log_file" xsi:type="File" fileName="${basedir}/logs/${shortdate}.log" 
  layout="${longdate} | ${level:uppercase=false} | ${message} ${onexception:${exception:format=tostring} ${newline} ${stacktrace} ${newline}" />
 </targets>
 <rules>
 <!--跳過所有級別的Microsoft組件的日志記錄-->
 <logger name="Microsoft.*" final="true" />
 <!-- BlackHole without writeTo -->
 <!--只通過數(shù)據(jù)庫記錄日志，如果給了name名字，cs里用日志記錄的時候，取logger需要把name當做參數(shù)-->
 <logger name="logdb" writeTo="log_database" />
 <logger name="logfile" writeTo="log_file" />
 </rules>
</nlog>

CREATE DATABASE IF NOT EXISTS `TestNLog`;
USE `TestNLog`;

-- Dumping structure for table TestNLog.TblLogrecords
CREATE TABLE IF NOT EXISTS `TblLogrecords` (
 `Id` int(11) NOT NULL AUTO_INCREMENT,
 `LogDate` datetime(6) NOT NULL,
 `LogLevel` varchar(50) NOT NULL,
 `LogType` varchar(50) DEFAULT NULL,
 `Logger` varchar(256) NOT NULL,
 `Message` longtext,
 `MachineName` varchar(50) DEFAULT NULL,
 `MachineIp` varchar(50) DEFAULT NULL,
 `NetRequestMethod` varchar(10) DEFAULT NULL,
 `NetRequestUrl` varchar(500) DEFAULT NULL,
 `NetUserIsauthenticated` varchar(10) DEFAULT NULL,
 `NetUserAuthtype` varchar(50) DEFAULT NULL,
 `NetUserIdentity` varchar(50) DEFAULT NULL,
 `Exception` longtext,
 PRIMARY KEY (`Id`)
) ENGINE=InnoDB AUTO_INCREMENT=96 DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci;

"ConectionStrings": {
 "MySqlConnection": "server=192.168.137.10;database=TestNLog;user=root;password=mysql@local"
 }

using NLog;
using NLog.Config;
using System;
using System.ComponentModel;
using System.Linq;
using System.Xml.Linq;

namespace NLogUsage.CommonUtils
{
 public enum LogType
 {
 [Description("網站")]
 Web,
 [Description("數(shù)據(jù)庫")]
 DataBase,
 [Description("Api接口")]
 ApiRequest,
 [Description("中間件")]
 Middleware
 }
 public static class NLogUtil
 {
 public static Logger dbLogger = LogManager.GetLogger("logdb");
 public static Logger fileLogger = LogManager.GetLogger("logfile");
 /// <summary>
 /// 寫日志到數(shù)據(jù)庫
 /// </summary>
 /// <param name="logLevel">日志等級</param>
 /// <param name="logType">日志類型</param>
 /// <param name="message">信息</param>
 /// <param name="exception">異常</param>
 public static void WriteDBLog(LogLevel logLevel, LogType logType, string message, Exception exception = null)
 {
  LogEventInfo theEvent = new LogEventInfo(logLevel, dbLogger.Name, message);
  theEvent.Properties["LogType"] = logType.ToString();
  theEvent.Exception = exception;
  dbLogger.Log(theEvent);
 }
 /// <summary>
 /// 寫日志到文件
 /// </summary>
 /// <param name="logLevel">日志等級</param>
 /// <param name="logType">日志類型</param>
 /// <param name="message">信息</param>
 /// <param name="exception">異常</param>
 public static void WriteFileLog(LogLevel logLevel, LogType logType, string message, Exception exception = null)
 {
  LogEventInfo theEvent = new LogEventInfo(logLevel, fileLogger.Name, message);
  theEvent.Properties["LogType"] = logType.ToString();
  theEvent.Exception = exception;
  fileLogger.Log(theEvent);
 }

 /// <summary>
 /// 確保NLog配置文件sql連接字符串正確
 /// </summary>
 /// <param name="nlogPath"></param>
 /// <param name="sqlConnectionStr"></param>
 public static void EnsureNlogConfig(string nlogPath, string sqlConnectionStr)
 {
  XDocument xd = XDocument.Load(nlogPath);
  if (xd.Root.Elements().FirstOrDefault(a => a.Name.LocalName == "targets")
  is XElement targetsNode && targetsNode != null &&
  targetsNode.Elements().FirstOrDefault(a => a.Name.LocalName == "target" && a.Attribute("name").Value == "log_database")
  is XElement targetNode && targetNode != null)
  {
  if (!targetNode.Attribute("connectionString").Value.Equals(sqlConnectionStr))//不一致則修改
  {
   //這里暫時沒有考慮dbProvider的變動
   targetNode.Attribute("connectionString").Value = sqlConnectionStr;
   xd.Save(nlogPath);
   //編輯后重新載入配置文件（不依靠NLog自己的autoReload，有延遲）
   LogManager.Configuration = new XmlLoggingConfiguration(nlogPath);
  }
  }
 }
 }
}

//using NLog.Web;
.ConfigureLogging(logging => { 
  logging.ClearProviders(); 
  logging.SetMinimumLevel(Microsoft.Extensions.Logging.LogLevel.Trace); 
  }).UseNLog(); // NLog: 依賴注入Nlog

//using NLogUsage.CommonUtils;
//using Microsoft.Extensions.DependencyInjection;
public static void Main(string[] args)
{
 //CreateHostBuilder(args).Build().Run();
 var host = CreateHostBuilder(args).Build();
 try
 {
 using (IServiceScope scope = host.Services.CreateScope())
 {
  IConfiguration configuration = scope.ServiceProvider.GetRequiredService<IConfiguration>();
  //獲取到appsettings.json中的連接字符串
  string sqlString = configuration.GetSection("ConectionStrings:MySqlConnection").Value;
  //確保NLog.config中連接字符串與appsettings.json中同步
  NLogUtil.EnsureNlogConfig("NLog.config", sqlString);
 }
 //throw new Exception("測試異常");//for test

 //其他項目啟動時需要做的事情
 //code
 NLogUtil.WriteDBLog(NLog.LogLevel.Trace, LogType.Web, "網站啟動成功");
 host.Run();
 }
 catch (Exception ex)
 {
 //使用nlog寫到本地日志文件（萬一數(shù)據(jù)庫沒創(chuàng)建/連接成功）
 string errorMessage = "網站啟動初始化數(shù)據(jù)異常";
 NLogUtil.WriteFileLog(NLog.LogLevel.Error, LogType.Web, errorMessage, new Exception(errorMessage, ex));
 NLogUtil.WriteDBLog(NLog.LogLevel.Error, LogType.Web, errorMessage, new Exception(errorMessage, ex));
 throw;
 }
}