asp.net core添加全局异常处理及log4net、Nlog应用

2021-10-09 22:46:30

整体架构目录：ASP.NET Core分布式项目实战-目录

一、介绍

此篇文章将会介绍项目的全局异常收集以及采用log4net或者NLog记录。

众所周知，一旦自己的项目报错，如果没有进行处理都是显示不友好的，有得甚至直接爆出错误页面，看的也是很奇怪。

为了避免出现这样的错误以及在错误出现的时候可以进行收集错误，供维护人员进行bug修改，因此需要进行全局异常的收集。

让我们开始部署吧。

此篇文章的目录

1、log4net使用

2、Nlog使用

后期将会把NLog+ELK进行结合部署收集我们的asp.net core的项目。大家可以拭目以待吧。

二、部署（log4net使用）

1、新建一个asp.net core webapi的项目

然后目前我先引入 log4net nuget包。

2、然后创建一个log4net.config文件

此文件中，我创建了一个是记录错误的文件夹（LogError）以及是记录操作的文件夹(LogInfo)，代码如下：我把需要记录的文件放在了log文件夹下面。

<?xml version="1.0" encoding="utf-8"?>
<configuration>
  <log4net>

&lt;!-- 错误日志类--&gt;
&lt;logger name=<span style="color: #800000;">"</span><span style="color: #800000;">logerror</span><span style="color: #800000;">"</span>&gt;
  &lt;level value=<span style="color: #800000;">"</span><span style="color: #800000;">ALL</span><span style="color: #800000;">"</span> /&gt;
  &lt;appender-<span style="color: #0000ff;">ref</span> <span style="color: #0000ff;">ref</span>=<span style="color: #800000;">"</span><span style="color: #800000;">ErrorAppender</span><span style="color: #800000;">"</span> /&gt;
&lt;/logger&gt;
&lt;!-- 错误日志附加介质--&gt;
&lt;appender name=<span style="color: #800000;">"</span><span style="color: #800000;">ErrorAppender</span><span style="color: #800000;">"</span> type=<span style="color: #800000;">"</span><span style="color: #800000;">log4net.Appender.RollingFileAppender</span><span style="color: #800000;">"</span>&gt;
  &lt;!--日志文件路径--&gt;
  &lt;param name=<span style="color: #800000;">"</span><span style="color: #800000;">File</span><span style="color: #800000;">"</span> value=<span style="color: #800000;">"</span><strong><span style="color: #ff0000;">Log\\LogError\\</span></strong><span style="color: #800000;">"</span> /&gt;
  &lt;!--是否是向文件中追加日志--&gt;
  &lt;param name=<span style="color: #800000;">"</span><span style="color: #800000;">AppendToFile</span><span style="color: #800000;">"</span> value=<span style="color: #800000;">"</span><span style="color: #800000;">true</span><span style="color: #800000;">"</span> /&gt;
  &lt;!--log保留天数--&gt;
  &lt;param name=<span style="color: #800000;">"</span><span style="color: #800000;">MaxSizeRollBackups</span><span style="color: #800000;">"</span> value=<span style="color: #800000;">"</span><span style="color: #800000;">1000</span><span style="color: #800000;">"</span> /&gt;
  &lt;!--最大文件大小--&gt;
  &lt;param name=<span style="color: #800000;">"</span><span style="color: #800000;">MaxFileSize</span><span style="color: #800000;">"</span> value=<span style="color: #800000;">"</span><span style="color: #800000;">10240</span><span style="color: #800000;">"</span> /&gt;
  &lt;!--日志文件名是否是固定不变的--&gt;
  &lt;param name=<span style="color: #800000;">"</span><span style="color: #800000;">StaticLogFileName</span><span style="color: #800000;">"</span> value=<span style="color: #800000;">"</span><span style="color: #800000;">false</span><span style="color: #800000;">"</span> /&gt;
  &lt;!--日志文件名格式为:<span style="color: #800080;">2008</span>-<span style="color: #800080;">08</span>-<span style="color: #800080;">31</span>.log--&gt;
  &lt;param name=<span style="color: #800000;">"</span><span style="color: #800000;">DatePattern</span><span style="color: #800000;">"</span> value=<span style="color: #800000;">"</span><span style="color: #800000;">yyyy-MM-dd&amp;quot;.htm&amp;quot;</span><span style="color: #800000;">"</span> /&gt;
  &lt;!--日志根据日期滚动--&gt;
  &lt;param name=<span style="color: #800000;">"</span><span style="color: #800000;">RollingStyle</span><span style="color: #800000;">"</span> value=<span style="color: #800000;">"</span><span style="color: #800000;">Date</span><span style="color: #800000;">"</span> /&gt;
  &lt;!--信息日志布局--&gt;
  &lt;layout type=<span style="color: #800000;">"</span><span style="color: #800000;">log4net.Layout.PatternLayout</span><span style="color: #800000;">"</span>&gt;
    &lt;param name=<span style="color: #800000;">"</span><span style="color: #800000;">ConversionPattern</span><span style="color: #800000;">"</span> value=<span style="color: #800000;">"</span><span style="color: #800000;">&amp;lt;HR COLOR=red&amp;gt;%n【异常时间】：%d [%t] &amp;lt;BR&amp;gt;%n【异常级别】：%-5p &amp;lt;BR&amp;gt;%n%m &amp;lt;BR&amp;gt;%n &amp;lt;HR Size=1&amp;gt;</span><span style="color: #800000;">"</span>  /&gt;
  &lt;/layout&gt;
&lt;/appender&gt;

&lt;!-- 信息日志类 --&gt;
&lt;logger name=<span style="color: #800000;">"</span><span style="color: #800000;">loginfo</span><span style="color: #800000;">"</span>&gt;
  &lt;level value=<span style="color: #800000;">"</span><span style="color: #800000;">ALL</span><span style="color: #800000;">"</span> /&gt;
  &lt;appender-<span style="color: #0000ff;">ref</span> <span style="color: #0000ff;">ref</span>=<span style="color: #800000;">"</span><span style="color: #800000;">InfoAppender</span><span style="color: #800000;">"</span> /&gt;
&lt;/logger&gt;
&lt;!-- 信息日志附加介质--&gt;
&lt;appender name=<span style="color: #800000;">"</span><span style="color: #800000;">InfoAppender</span><span style="color: #800000;">"</span> type=<span style="color: #800000;">"</span><span style="color: #800000;">log4net.Appender.RollingFileAppender</span><span style="color: #800000;">"</span>&gt;
  &lt;!--日志文件路径--&gt;
  &lt;param name=<span style="color: #800000;">"</span><span style="color: #800000;">File</span><span style="color: #800000;">"</span> value=<span style="color: #800000;">"</span><strong><span style="color: #ff0000;">Log\\LogInfo\\</span></strong><span style="color: #800000;">"</span> /&gt;
  &lt;!--是否是向文件中追加日志--&gt;
  &lt;param name=<span style="color: #800000;">"</span><span style="color: #800000;">AppendToFile</span><span style="color: #800000;">"</span> value=<span style="color: #800000;">"</span><span style="color: #800000;">true</span><span style="color: #800000;">"</span> /&gt;
  &lt;!--log保留天数--&gt;
  &lt;param name=<span style="color: #800000;">"</span><span style="color: #800000;">MaxSizeRollBackups</span><span style="color: #800000;">"</span> value=<span style="color: #800000;">"</span><span style="color: #800000;">100</span><span style="color: #800000;">"</span> /&gt;
  &lt;param name=<span style="color: #800000;">"</span><span style="color: #800000;">MaxFileSize</span><span style="color: #800000;">"</span> value=<span style="color: #800000;">"</span><span style="color: #800000;">1</span><span style="color: #800000;">"</span> /&gt;
  &lt;!--日志文件名是否是固定不变的--&gt;
  &lt;param name=<span style="color: #800000;">"</span><span style="color: #800000;">StaticLogFileName</span><span style="color: #800000;">"</span> value=<span style="color: #800000;">"</span><span style="color: #800000;">false</span><span style="color: #800000;">"</span> /&gt;
  &lt;!--日志文件名格式为:<span style="color: #800080;">2008</span>-<span style="color: #800080;">08</span>-<span style="color: #800080;">31</span>.log--&gt;
  &lt;param name=<span style="color: #800000;">"</span><span style="color: #800000;">DatePattern</span><span style="color: #800000;">"</span> value=<span style="color: #800000;">"</span><span style="color: #800000;">yyyy-MM-dd&amp;quot;.htm&amp;quot;</span><span style="color: #800000;">"</span> /&gt;
  &lt;!--日志根据日期滚动--&gt;
  &lt;param name=<span style="color: #800000;">"</span><span style="color: #800000;">RollingStyle</span><span style="color: #800000;">"</span> value=<span style="color: #800000;">"</span><span style="color: #800000;">Date</span><span style="color: #800000;">"</span> /&gt;
  &lt;!--信息日志布局--&gt;
  &lt;layout type=<span style="color: #800000;">"</span><span style="color: #800000;">log4net.Layout.PatternLayout</span><span style="color: #800000;">"</span>&gt;
    &lt;param name=<span style="color: #800000;">"</span><span style="color: #800000;">ConversionPattern</span><span style="color: #800000;">"</span> value=<span style="color: #800000;">"</span><span style="color: #800000;">&amp;lt;HR COLOR=blue&amp;gt;%n日志时间：%d [%t] &amp;lt;BR&amp;gt;%n日志级别：%-5p &amp;lt;BR&amp;gt;%n%m &amp;lt;BR&amp;gt;%n &amp;lt;HR Size=1&amp;gt;</span><span style="color: #800000;">"</span>  /&gt;
  &lt;/layout&gt;
&lt;/appender&gt;

</log4net>

<!--
<system.webServer>

&lt;handlers&gt;
  &lt;remove name=<span style="color: #800000;">"</span><span style="color: #800000;">aspNetCore</span><span style="color: #800000;">"</span>/&gt;
  &lt;add name=<span style="color: #800000;">"</span><span style="color: #800000;">aspNetCore</span><span style="color: #800000;">"</span> path=<span style="color: #800000;">"</span><span style="color: #800000;">*</span><span style="color: #800000;">"</span> verb=<span style="color: #800000;">"</span><span style="color: #800000;">*</span><span style="color: #800000;">"</span> modules=<span style="color: #800000;">"</span><span style="color: #800000;">AspNetCoreModule</span><span style="color: #800000;">"</span> resourceType=<span style="color: #800000;">"</span><span style="color: #800000;">Unspecified</span><span style="color: #800000;">"</span>/&gt;
&lt;/handlers&gt;
&lt;aspNetCore processPath=<span style="color: #800000;">"</span><span style="color: #800000;">%LAUNCHER_PATH%</span><span style="color: #800000;">"</span> arguments=<span style="color: #800000;">"</span><span style="color: #800000;">%LAUNCHER_ARGS%</span><span style="color: #800000;">"</span> stdoutLogEnabled=<span style="color: #800000;">"</span><span style="color: #800000;">false</span><span style="color: #800000;">"</span> stdoutLogFile=<span style="color: #800000;">"</span><span style="color: #800000;">.\logs\stdout</span><span style="color: #800000;">"</span> /&gt;

</system.webServer>
-->

</configuration>

3、在asp.net core项目中 Startup.cs 中需要添加初始化log4net的仓储名，主要是用来给log4net标记一个名称，这边可以随意。

4、在项目中创建一个类用来记录log的日志格式以及数据分类存放

创建LogHelper.cs,

定义log格式，当然自己可以随意定义哈。

#region 全局异常错误记录持久化

    <span style="color: #808080;">///</span> <span style="color: #808080;">&lt;summary&gt;</span>
    <span style="color: #808080;">///</span><span style="color: #008000;"> 全局异常错误记录持久化
    </span><span style="color: #808080;">///</span> <span style="color: #808080;">&lt;/summary&gt;</span>
    <span style="color: #808080;">///</span> <span style="color: #808080;">&lt;param name="throwMsg"&gt;&lt;/param&gt;</span>
    <span style="color: #808080;">///</span> <span style="color: #808080;">&lt;param name="ex"&gt;&lt;/param&gt;</span>
    <span style="color: #0000ff;">public</span> <span style="color: #0000ff;">static</span> <span style="color: #0000ff;">void</span> ErrorLog(<span style="color: #0000ff;">string</span><span style="color: #000000;"> throwMsg, Exception ex)
    {
        </span><span style="color: #0000ff;">string</span> errorMsg = <span style="color: #0000ff;">string</span>.Format(<span style="color: #800000;">"</span><span style="color: #800000;">【抛出信息】：{0} &lt;br&gt;【异常类型】：{1} &lt;br&gt;【异常信息】：{2} &lt;br&gt;【堆栈调用】：{3}</span><span style="color: #800000;">"</span>, <span style="color: #0000ff;">new</span> <span style="color: #0000ff;">object</span><span style="color: #000000;">[] { throwMsg,
            ex.GetType().Name, ex.Message, ex.StackTrace });
        errorMsg </span>= errorMsg.Replace(<span style="color: #800000;">"</span><span style="color: #800000;">\r\n</span><span style="color: #800000;">"</span>, <span style="color: #800000;">"</span><span style="color: #800000;">&lt;br&gt;</span><span style="color: #800000;">"</span><span style="color: #000000;">);
        errorMsg </span>= errorMsg.Replace(<span style="color: #800000;">"</span><span style="color: #800000;">位置</span><span style="color: #800000;">"</span>, <span style="color: #800000;">"</span><span style="color: #800000;">&lt;strong style=\"color:red\"&gt;位置&lt;/strong&gt;</span><span style="color: #800000;">"</span><span style="color: #000000;">);
        logerror.Error(errorMsg);
    }
    </span><span style="color: #0000ff;">#endregion</span></pre>

#region 自定义操作记录

    <span style="color: #808080;">///</span> <span style="color: #808080;">&lt;summary&gt;</span>
    <span style="color: #808080;">///</span><span style="color: #008000;"> 自定义操作记录，与仓储中的增删改的日志是记录同一张表
    </span><span style="color: #808080;">///</span> <span style="color: #808080;">&lt;/summary&gt;</span>
    <span style="color: #808080;">///</span> <span style="color: #808080;">&lt;param name="throwMsg"&gt;&lt;/param&gt;</span>
    <span style="color: #808080;">///</span> <span style="color: #808080;">&lt;param name="ex"&gt;&lt;/param&gt;</span>
    <span style="color: #0000ff;">public</span> <span style="color: #0000ff;">static</span> <span style="color: #0000ff;">void</span> WriteLog(<span style="color: #0000ff;">string</span><span style="color: #000000;"> throwMsg, Exception ex)
    {
        </span><span style="color: #0000ff;">string</span> errorMsg = <span style="color: #0000ff;">string</span>.Format(<span style="color: #800000;">"</span><span style="color: #800000;">【抛出信息】：{0} &lt;br&gt;【异常类型】：{1} &lt;br&gt;【异常信息】：{2} &lt;br&gt;【堆栈调用】：{3}</span><span style="color: #800000;">"</span>, <span style="color: #0000ff;">new</span> <span style="color: #0000ff;">object</span><span style="color: #000000;">[] { throwMsg,
            ex.GetType().Name, ex.Message, ex.StackTrace });
        errorMsg </span>= errorMsg.Replace(<span style="color: #800000;">"</span><span style="color: #800000;">\r\n</span><span style="color: #800000;">"</span>, <span style="color: #800000;">"</span><span style="color: #800000;">&lt;br&gt;</span><span style="color: #800000;">"</span><span style="color: #000000;">);
        errorMsg </span>= errorMsg.Replace(<span style="color: #800000;">"</span><span style="color: #800000;">位置</span><span style="color: #800000;">"</span>, <span style="color: #800000;">"</span><span style="color: #800000;">&lt;strong style=\"color:red\"&gt;位置&lt;/strong&gt;</span><span style="color: #800000;">"</span><span style="color: #000000;">);
        logerror.Error(errorMsg);
    }
    </span><span style="color: #0000ff;">#endregion</span></pre>

5、有了以上的log格式，这样我就开始定义一下全局异常处理吧

我这边先创建一个全局异常处理类 GlobalExceptions.cs 然后需要在startup.cs中注入

在ConfigureServices 方法中注入。

//注入全局异常捕获
services.AddMvc(o =>
{
o.Filters.Add(typeof(GlobalExceptions));
});

6、GlobalExceptions类中添加处理，当然异常需要继承IExceptionFilter。

代码如下：

GlobalExceptions

public class GlobalExceptions : IExceptionFilter

{
    </span><span style="color: #0000ff;">private</span> <span style="color: #0000ff;">readonly</span><span style="color: #000000;"> IHostingEnvironment _env;
    </span><span style="color: #0000ff;">public</span><span style="color: #000000;"> GlobalExceptions(IHostingEnvironment env)
    {
        _env </span>=<span style="color: #000000;"> env;
    }
    </span><span style="color: #0000ff;">public</span> <span style="color: #0000ff;">void</span><span style="color: #000000;"> OnException(ExceptionContext context)
    {
        </span><span style="color: #0000ff;">var</span> json = <span style="color: #0000ff;">new</span><span style="color: #000000;"> JsonErrorResponse();
        </span><span style="color: #008000;">//</span><span style="color: #008000;">这里面是自定义的操作记录日志</span>
        <span style="color: #0000ff;">if</span> (context.Exception.GetType() == <span style="color: #0000ff;">typeof</span><span style="color: #000000;">(UserOperationException))
        {
            json.Message </span>=<span style="color: #000000;"> context.Exception.Message;
            </span><span style="color: #0000ff;">if</span><span style="color: #000000;"> (_env.IsDevelopment())
            {
                json.DevelopmentMessage </span>= context.Exception.StackTrace;<span style="color: #008000;">//</span><span style="color: #008000;">堆栈信息</span>

}

            context.Result </span>= <span style="color: #0000ff;">new</span> BadRequestObjectResult(json);<span style="color: #008000;">//</span><span style="color: #008000;">返回异常数据</span>

}

        </span><span style="color: #0000ff;">else</span><span style="color: #000000;">
        {
            json.Message </span>= <span style="color: #800000;">"</span><span style="color: #800000;">发生了未知内部错误</span><span style="color: #800000;">"</span><span style="color: #000000;">;
            </span><span style="color: #0000ff;">if</span><span style="color: #000000;"> (_env.IsDevelopment())
            {
                json.DevelopmentMessage </span>= context.Exception.StackTrace;<span style="color: #008000;">//</span><span style="color: #008000;">堆栈信息</span>

}

            context.Result </span>= <span style="color: #0000ff;">new</span><span style="color: #000000;"> InternalServerErrorObjectResult(json);
        }

        </span><span style="color: #008000;">//</span><span style="color: #008000;">采用log4net 进行错误日志记录</span>

LogHelper.ErrorLog(json.Message, context.Exception);

    }
}
</span><span style="color: #0000ff;">public</span> <span style="color: #0000ff;">class</span><span style="color: #000000;"> InternalServerErrorObjectResult : ObjectResult
{
    </span><span style="color: #0000ff;">public</span> InternalServerErrorObjectResult(<span style="color: #0000ff;">object</span> value) : <span style="color: #0000ff;">base</span><span style="color: #000000;">(value)
    {
        StatusCode </span>=<span style="color: #000000;"> StatusCodes.Status500InternalServerError;
    }
}</span></pre>

JsonErrorResponse.cs

public class JsonErrorResponse

{
    </span><span style="color: #808080;">///</span> <span style="color: #808080;">&lt;summary&gt;</span>
    <span style="color: #808080;">///</span><span style="color: #008000;"> 生产环境的消息
    </span><span style="color: #808080;">///</span> <span style="color: #808080;">&lt;/summary&gt;</span>
    <span style="color: #0000ff;">public</span> <span style="color: #0000ff;">string</span> Message { <span style="color: #0000ff;">get</span>; <span style="color: #0000ff;">set</span><span style="color: #000000;">; }
    </span><span style="color: #808080;">///</span> <span style="color: #808080;">&lt;summary&gt;</span>
    <span style="color: #808080;">///</span><span style="color: #008000;"> 开发环境的消息
    </span><span style="color: #808080;">///</span> <span style="color: #808080;">&lt;/summary&gt;</span>
    <span style="color: #0000ff;">public</span> <span style="color: #0000ff;">string</span> DevelopmentMessage { <span style="color: #0000ff;">get</span>; <span style="color: #0000ff;">set</span><span style="color: #000000;">; }
}</span></pre>

UserOperationException.cs

/// <summary>

<span style="color: #808080;">///</span><span style="color: #008000;"> 操作日志
</span><span style="color: #808080;">///</span> <span style="color: #808080;">&lt;/summary&gt;</span>
<span style="color: #0000ff;">public</span> <span style="color: #0000ff;">class</span><span style="color: #000000;"> UserOperationException : Exception
{
    </span><span style="color: #0000ff;">public</span><span style="color: #000000;"> UserOperationException() { }
    </span><span style="color: #0000ff;">public</span> UserOperationException(<span style="color: #0000ff;">string</span> message) : <span style="color: #0000ff;">base</span><span style="color: #000000;">(message) { }
    </span><span style="color: #0000ff;">public</span> UserOperationException(<span style="color: #0000ff;">string</span> message, Exception innerException) : <span style="color: #0000ff;">base</span><span style="color: #000000;">(message, innerException) { }
}</span></pre>

自此，全局异常配置完成，然后我们可以测试一下，随便写一个除以0的代码在日志记录中就会出现如下的展示：

哇，发现我的错误日志的格式非常的清楚，当然这个跟我的做事态度以及性格有很大的关系的啦，毕竟楼主还是很帅的。哈哈哈。

三、NLog使用

1、在项目中添加nlog的nuget包引入，“NLog.Web.AspNetCore”

2、创建nlog.config文件，大家会发现我的log格式跟上面的格式操作，而且我的分层层次也很清楚。哈哈.

<?xml version="1.0" encoding="utf-8" ?>
<nlog xmlns="http://www.nlog-project.org/schemas/NLog.xsd style="color: #800000;">"

  xmlns:xsi</span>=<span style="color: #800000;">"</span><span style="color: #800000;">http://www.w3.org/2001/XMLSchema-instance</span><span style="color: #800000;">"</span><span style="color: #000000;">
  autoReload</span>=<span style="color: #800000;">"</span><span style="color: #800000;">true</span><span style="color: #800000;">"</span>&gt;

<targets>

&lt;!-- 输出到文件,这个文件记录所有的日志 --&gt;
&lt;target xsi:type=<span style="color: #800000;">"</span><span style="color: #800000;">File</span><span style="color: #800000;">"</span> name=<span style="color: #800000;">"</span><span style="color: #800000;">allfile</span><span style="color: #800000;">"</span> fileName=<span style="color: #800000;">"</span><span style="color: #800000;">Log\LogAll\${shortdate}.htm</span><span style="color: #800000;">"</span><span style="color: #000000;">
            layout</span>=<span style="color: #800000;">"</span><span style="color: #800000;">&amp;lt;HR COLOR=red&amp;gt;${longdate}&amp;lt;BR&amp;gt;${logger}&amp;lt;BR&amp;gt;${uppercase:${level}}&amp;lt;BR&amp;gt;${message} ${exception}&amp;lt;HR Size=1&amp;gt;</span><span style="color: #800000;">"</span> /&gt;

&lt;!-- 输出到文件,这个文件记录错误日志 --&gt;
&lt;target xsi:type=<span style="color: #800000;">"</span><span style="color: #800000;">File</span><span style="color: #800000;">"</span> name=<span style="color: #800000;">"</span><span style="color: #800000;">logError</span><span style="color: #800000;">"</span> fileName=<span style="color: #800000;">"</span><span style="color: #800000;">Log\LogError\${shortdate}.htm</span><span style="color: #800000;">"</span><span style="color: #000000;">
        layout</span>=<span style="color: #800000;">"</span><span style="color: #800000;">&amp;lt;HR COLOR=red&amp;gt;【异常时间】：${date} &amp;lt;BR&amp;gt;【异常级别】：${level:uppercase=true} &amp;lt;BR&amp;gt;${message}&amp;lt;HR Size=1&amp;gt;</span><span style="color: #800000;">"</span> /&gt;

&lt;!-- 输出到文件,这个文件记录操作日志 --&gt;
&lt;target xsi:type=<span style="color: #800000;">"</span><span style="color: #800000;">File</span><span style="color: #800000;">"</span> name=<span style="color: #800000;">"</span><span style="color: #800000;">logInfo</span><span style="color: #800000;">"</span> fileName=<span style="color: #800000;">"</span><span style="color: #800000;">Log\LogInfo\${shortdate}.htm</span><span style="color: #800000;">"</span><span style="color: #000000;">
             layout</span>=<span style="color: #800000;">"</span><span style="color: #800000;">&amp;lt;HR COLOR=red&amp;gt;【操作时间】：${date} &amp;lt;BR&amp;gt;【操作级别】：${level:uppercase=true} &amp;lt;BR&amp;gt;${message}&amp;lt;HR Size=1&amp;gt;</span><span style="color: #800000;">"</span> /&gt;

</targets>

<rules>

&lt;!--All logs, including <span style="color: #0000ff;">from</span> Microsoft--&gt;
&lt;logger name=<span style="color: #800000;">"</span><span style="color: #800000;">*</span><span style="color: #800000;">"</span> minlevel=<span style="color: #800000;">"</span><span style="color: #800000;">Trace</span><span style="color: #800000;">"</span> writeTo=<span style="color: #800000;">"</span><span style="color: #800000;">allfile</span><span style="color: #800000;">"</span> /&gt;
&lt;logger name=<span style="color: #800000;">"</span><span style="color: #800000;">*</span><span style="color: #800000;">"</span> minlevel=<span style="color: #800000;">"</span><span style="color: #800000;">Error</span><span style="color: #800000;">"</span> writeTo=<span style="color: #800000;">"</span><span style="color: #800000;">logError</span><span style="color: #800000;">"</span> /&gt;
&lt;logger name=<span style="color: #800000;">"</span><span style="color: #800000;">*</span><span style="color: #800000;">"</span> minlevel=<span style="color: #800000;">"</span><span style="color: #800000;">Info</span><span style="color: #800000;">"</span> writeTo=<span style="color: #800000;">"</span><span style="color: #800000;">logInfo</span><span style="color: #800000;">"</span> /&gt;
&lt;logger name=<span style="color: #800000;">"</span><span style="color: #800000;">Microsoft.*</span><span style="color: #800000;">"</span> maxLevel=<span style="color: #800000;">"</span><span style="color: #800000;">Info</span><span style="color: #800000;">"</span> final=<span style="color: #800000;">"</span><span style="color: #800000;">true</span><span style="color: #800000;">"</span> /&gt;

</rules>
</nlog>

注：然后将此文件点击右键，选择属性，把复制输出目录修改为“始终复制”，无法不修改，则会无法加载此文件。

3、在startup.cs中的 Configure方法注入

//ILoggerFactory loggerFactory
loggerFactory.AddNLog();
NLog.LogManager.LoadConfiguration("nlog.config"); //填入上面创建的文件的名称

然后运行以下即可看到在bin/debug下面生成文件夹

4、创建NLogHelp.cs类

public class NLogHelp

{
    </span><span style="color: #0000ff;">public</span> <span style="color: #0000ff;">static</span> Logger logger =<span style="color: #000000;"> LogManager.GetCurrentClassLogger();
    </span><span style="color: #0000ff;">public</span> <span style="color: #0000ff;">static</span> <span style="color: #0000ff;">void</span> ErrorLog(<span style="color: #0000ff;">string</span><span style="color: #000000;"> throwMsg, Exception ex)
    {
        </span><span style="color: #0000ff;">string</span> errorMsg = <span style="color: #0000ff;">string</span>.Format(<span style="color: #800000;">"</span><span style="color: #800000;">【异常信息】：{0} &lt;br&gt;【异常类型】：{1} &lt;br&gt;【堆栈调用】：{2}</span><span style="color: #800000;">"</span><span style="color: #000000;">,
            </span><span style="color: #0000ff;">new</span> <span style="color: #0000ff;">object</span><span style="color: #000000;">[] { throwMsg, ex.GetType().Name, ex.StackTrace });
        errorMsg </span>= errorMsg.Replace(<span style="color: #800000;">"</span><span style="color: #800000;">\r\n</span><span style="color: #800000;">"</span>, <span style="color: #800000;">"</span><span style="color: #800000;">&lt;br&gt;</span><span style="color: #800000;">"</span><span style="color: #000000;">);
        errorMsg </span>= errorMsg.Replace(<span style="color: #800000;">"</span><span style="color: #800000;">位置</span><span style="color: #800000;">"</span>, <span style="color: #800000;">"</span><span style="color: #800000;">&lt;strong style=\"color:red\"&gt;位置&lt;/strong&gt;</span><span style="color: #800000;">"</span><span style="color: #000000;">);
        logger.Error(errorMsg);
    }
    </span><span style="color: #0000ff;">public</span> <span style="color: #0000ff;">static</span> <span style="color: #0000ff;">void</span> InfoLog(<span style="color: #0000ff;">string</span><span style="color: #000000;"> operateMsg)
    {
        </span><span style="color: #0000ff;">string</span> errorMsg = <span style="color: #0000ff;">string</span>.Format(<span style="color: #800000;">"</span><span style="color: #800000;">【操作信息】：{0} &lt;br&gt;</span><span style="color: #800000;">"</span><span style="color: #000000;">,
            </span><span style="color: #0000ff;">new</span> <span style="color: #0000ff;">object</span><span style="color: #000000;">[] { operateMsg });
        errorMsg </span>= errorMsg.Replace(<span style="color: #800000;">"</span><span style="color: #800000;">\r\n</span><span style="color: #800000;">"</span>, <span style="color: #800000;">"</span><span style="color: #800000;">&lt;br&gt;</span><span style="color: #800000;">"</span><span style="color: #000000;">);
        logger.Info(errorMsg);
    }
}</span></pre>

5、在上面log4net中的GlobalExceptions类把

LogHelper.ErrorLog(json.Message, context.Exception)替换成如下：NLogHelp.ErrorLog(json.Message,context.Exception)即可。

运行测试如下：

【异常时间】：2018/09/03 14:41:36.786 
【异常级别】：ERROR 
【异常信息】：错误消息：Failed to create instance of type
at AspectCore.Injector.ServiceCallSiteResolver.ResolvePropertyInject(ServiceDefinition service)
【异常类型】：InvalidOperationException 
【堆栈调用】： at AspectCore.Injector.ServiceCallSiteResolver.ResolveTypeService(TypeServiceDefinition typeServiceDefinition)
at AspectCore.Injector.ServiceCallSiteResolver.ResolvePropertyInject(ServiceDefinition service)
at System.Collections.Concurrent.ConcurrentDictionary</span><span style="color: #800080;">2</span>.GetOrAdd(TKey key, Func2 valueFactory)
at AspectCore.Injector.ServiceResolver.b

自此，完美搞定，等后期我将会介绍采用ELK+NLog进行数据采集及展示，请大家拭目以待吧。

文章转载自阿里云 MVP郭联钰，查看原文

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