添加Nuget引用
需要添加两个Nuget引用：NLog.Web.AspNetCore和NLog.Targets.ElasticSearch
配置
新增nlog.config配置文件，并设置属性生成操作为内容，复制到输出目录为始终复制，内容如下。
<?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" ?????internalLogToConsole="true"> ?<extensions> ???<add assembly="NLog.Targets.ElasticSearch"/> ?</extensions> ?<targets> ???<!--ElasticSearch保存日志信息--> ???<target name="ElasticSearch" xsi:type="ElasticSearch" ConnectionStringName="ElasticSearchServerAddress" ?????????????index="userapi-${date:format=yyyy.MM.dd}" documentType="doc" includeAllProperties="true" ????????????????layout="[${date:format=yyyy-MM-dd HH\:mm\:ss}][${level}] ${logger} ${message} ${exception:format=toString}"> ?????<field name="MachineName" layout="${machinename}" /> ?????<field name="Time" layout="${longdate}" /> ?????<field name="level" layout="${level:uppercase=true}" /> ?????<field name="logger" layout=" ${logger}" /> ?????<field name="message" layout=" ${message}" /> ?????<field name="exception" layout=" ${exception:format=toString}" /> ?????<field name="processid" layout=" ${processid}" /> ?????<field name="threadname" layout=" ${threadname}" /> ?????<field name="stacktrace" layout=" ${stacktrace}" /> ?????<field name="Properties" layout="${machinename} ${longdate} ${level:uppercase=true} ${logger} ${message} ${exception}|${processid}|${stacktrace}|${threadname}" /> ???</target> ?</targets> ?<rules> ???<logger name="*" minlevel="INFO" writeTo="ElasticSearch" /> ?</rules></nlog>修改appsettings.json，增加如下节点，注意，经调试源码才发现，这里必须将连接增加到ConnectionStrings节点下，ElasticSearchServerAddress节点名称对应nlog.config中ConnectionStringName的名称。
"ConnectionStrings": { ???"ElasticSearchServerAddress": "http://192.168.2.97:9200,http://192.168.2.101:9200,http://192.168.2.102:9200"}修改代码
修改Program.cs文件：
public static void Main(string[] args){ ?????NLogBuilder.ConfigureNLog("nlog.config"); ?????BuildWebHost(args).Run(); }public static IWebHost BuildWebHost(string[] args) => ???????????WebHost.CreateDefaultBuilder(args) ???????????????.UseNLog() ???????????????.UseStartup<Startup>() ???????????????.Build();修改Startup.cs文件：
public void Configure(IApplicationBuilder app, IHostingEnvironment env, ILoggerFactory loggerFactory){ ??loggerFactory.AddNLog();}测试
???public class ValuesController : Controller ???{ ???????private ILogger _logger; ???????public ValuesController(ILogger<ValuesController> logger) ???????{ ???????????_logger = logger; ???????} ???????[HttpGet] ???????public IEnumerable<string> Get() ???????{ ???????????_logger.LogInformation("测试一下，不要紧张!"); ???????????return new string[] { "value1", "value2" }; ???????}}kibana里查询截图：
.net core使用NLog+Elasticsearch记录日志
原文地址：https://www.cnblogs.com/focus-lei/p/9154867.html