缘起
哈喽我是不定期更新的日常，昨天群里小伙伴问到了记录日志，当然，以前我也挖过这个坑，后来一直没有来得及填上，也想着 swagger 一直又有错误信息展示的功能，就迟迟没有添加这个功能，不过昨天夜里想了想，还是需要增加上，旨在提高框架的高效性。不定期日常就直接上代码了，我有一个小想法，就是希望大家有好的想法，可以给我说，我会整理下，添加到框架里，并在文章头里写上
投稿作者：这里重点说明下，是参考群里小伙伴HelloWorld! 的相关内容，并在他的基础上更新，添加了注入和全局，大家可以看看他的文章，支持开源，棒棒哒。
废话不多，直接来看，最终的效果是这样的：
一、添加日志接口类
在 Blog.core 下的 Log 文件夹内，新建ILoggerHelper.cs
namespace Blog.Core.Log{ ???/// <summary> ???/// 日志接口 ???/// </summary> ???public interface ILoggerHelper ???{ ??????????????/// <summary> ???????/// 调试信息 ???????/// </summary> ???????/// <param name="source">source</param> ???????/// <param name="message">message</param> ???????void Debug(object source, string message); ???????/// <summary> ???????/// 调试信息 ???????/// </summary> ???????/// <param name="source">source</param> ???????/// <param name="message">message</param> ???????/// <param name="ps">ps</param> ???????void Debug(object source, string message, params object[] ps); ???????/// <summary> ???????/// 调试信息 ???????/// </summary> ???????/// <param name="source">source</param> ???????/// <param name="message">message</param> ???????void Debug(Type source, string message); ???????/// <summary> ???????/// 关键信息 ???????/// </summary> ???????/// <param name="source">source</param> ???????/// <param name="message">message</param> ???????void Info(object source, object message); ???????/// <summary> ???????/// 关键信息 ???????/// </summary> ???????/// <param name="source">source</param> ???????/// <param name="message">message</param> ???????void Info(Type source, object message); ???????/// <summary> ???????/// 警告信息 ???????/// </summary> ???????/// <param name="source">source</param> ???????/// <param name="message">message</param> ???????void Warn(object source, object message); ???????/// <summary> ???????/// 警告信息 ???????/// </summary> ???????/// <param name="source">source</param> ???????/// <param name="message">message</param> ???????void Warn(Type source, object message); ???????/// <summary> ???????/// 错误信息 ???????/// </summary> ???????/// <param name="source">source</param> ???????/// <param name="message">message</param> ???????void Error(object source, object message); ???????/// <summary> ???????/// 错误信息 ???????/// </summary> ???????/// <param name="source">source</param> ???????/// <param name="message">message</param> ???????void Error(Type source, object message); ???????/// <summary> ???????/// 失败信息 ???????/// </summary> ???????/// <param name="source">source</param> ???????/// <param name="message">message</param> ???????void Fatal(object source, object message); ???????/// <summary> ???????/// 失败信息 ???????/// </summary> ???????/// <param name="source">source</param> ???????/// <param name="message">message</param> ???????void Fatal(Type source, object message); ???????/* Log a message object and exception */ ???????/// <summary> ???????/// 调试信息 ???????/// </summary> ???????/// <param name="source">source</param> ???????/// <param name="message">message</param> ???????/// <param name="exception">ex</param> ???????void Debug(object source, object message, Exception exception); ???????/// <summary> ???????/// 调试信息 ???????/// </summary> ???????/// <param name="source">source</param> ???????/// <param name="message">message</param> ???????/// <param name="exception">ex</param> ???????void Debug(Type source, object message, Exception exception); ???????/// <summary> ???????/// 关键信息 ???????/// </summary> ???????/// <param name="source">source</param> ???????/// <param name="message">message</param> ???????/// <param name="exception">ex</param> ???????void Info(object source, object message, Exception exception); ???????/// <summary> ???????/// 关键信息 ???????/// </summary> ???????/// <param name="source">source</param> ???????/// <param name="message">message</param> ???????/// <param name="exception">ex</param> ???????void Info(Type source, object message, Exception exception); ???????/// <summary> ???????/// 警告信息 ???????/// </summary> ???????/// <param name="source">source</param> ???????/// <param name="message">message</param> ???????/// <param name="exception">ex</param> ???????void Warn(object source, object message, Exception exception); ???????/// <summary> ???????/// 警告信息 ???????/// </summary> ???????/// <param name="source">source</param> ???????/// <param name="message">message</param> ???????/// <param name="exception">ex</param> ???????void Warn(Type source, object message, Exception exception); ???????/// <summary> ???????/// 错误信息 ???????/// </summary> ???????/// <param name="source">source</param> ???????/// <param name="message">message</param> ???????/// <param name="exception">ex</param> ???????void Error(object source, object message, Exception exception); ???????/// <summary> ???????/// 错误信息 ???????/// </summary> ???????/// <param name="source">source</param> ???????/// <param name="message">message</param> ???????/// <param name="exception">ex</param> ???????void Error(Type source, object message, Exception exception); ???????/// <summary> ???????/// 失败信息 ???????/// </summary> ???????/// <param name="source">source</param> ???????/// <param name="message">message</param> ???????/// <param name="exception">ex</param> ???????void Fatal(object source, object message, Exception exception); ???????/// <summary> ???????/// 失败信息 ???????/// </summary> ???????/// <param name="source">source</param> ???????/// <param name="message">message</param> ???????/// <param name="exception">ex</param> ???????void Fatal(Type source, object message, Exception exception); ???}}二、实现日志帮助类，引入log4net
1、在 Log 文件夹下新建LogHelper.cs
namespace Blog.Core.Log{ ???/// <summary> ???/// 日志帮助实现类 ???/// </summary> ???public class LogHelper : ILoggerHelper ???{ ???????private readonly ConcurrentDictionary<Type, ILog> Loggers = new ConcurrentDictionary<Type, ILog>(); ???????/// <summary> ???????/// 获取记录器 ???????/// </summary> ???????/// <param name="source">soruce</param> ???????/// <returns></returns> ???????private ILog GetLogger(Type source) ???????{ ???????????if (Loggers.ContainsKey(source)) ???????????{ ???????????????return Loggers[source]; ???????????} ???????????else ???????????{ ???????????????ILog logger = LogManager.GetLogger(Startup.repository.Name, source); ???????????????Loggers.TryAdd(source, logger); ???????????????return logger; ???????????} ???????} ???????/* Log a message object */ ???????/// <summary> ???????/// 调试信息 ???????/// </summary> ???????/// <param name="source">source</param> ???????/// <param name="message">message</param> ???????public void Debug(object source, string message) ???????{ ???????????Debug(source.GetType(), message); ???????} ???????/// <summary> ???????/// 调试信息 ???????/// </summary> ???????/// <param name="source">source</param> ???????/// <param name="message">message</param> ???????/// <param name="ps">ps</param> ???????public void Debug(object source, string message, params object[] ps) ???????{ ???????????Debug(source.GetType(), string.Format(message, ps)); ???????} ???????/// <summary> ???????/// 调试信息 ???????/// </summary> ???????/// <param name="source">source</param> ???????/// <param name="message">message</param> ???????public void Debug(Type source, string message) ???????{ ???????????ILog logger = GetLogger(source); ???????????if (logger.IsDebugEnabled) ???????????{ ???????????????logger.Debug(message); ???????????} ???????} ???????/// <summary> ???????/// 关键信息 ???????/// </summary> ???????/// <param name="source">source</param> ???????/// <param name="message">message</param> ???????public void Info(object source, object message) ???????{ ???????????Info(source.GetType(), message); ???????} ???????/// <summary> ???????/// 关键信息 ???????/// </summary> ???????/// <param name="source">source</param> ???????/// <param name="message">message</param> ???????public void Info(Type source, object message) ???????{ ???????????ILog logger = GetLogger(source); ???????????if (logger.IsInfoEnabled) ???????????{ ???????????????logger.Info(message); ???????????} ???????} ???????/// <summary> ???????/// 警告信息 ???????/// </summary> ???????/// <param name="source">source</param> ???????/// <param name="message">message</param> ???????public void Warn(object source, object message) ???????{ ???????????Warn(source.GetType(), message); ???????} ???????/// <summary> ???????/// 警告信息 ???????/// </summary> ???????/// <param name="source">source</param> ???????/// <param name="message">message</param> ???????public void Warn(Type source, object message) ???????{ ???????????ILog logger = GetLogger(source); ???????????if (logger.IsWarnEnabled) ???????????{ ???????????????logger.Warn(message); ???????????} ???????} ???????/// <summary> ???????/// 错误信息 ???????/// </summary> ???????/// <param name="source">source</param> ???????/// <param name="message">message</param> ???????public void Error(object source, object message) ???????{ ???????????Error(source.GetType(), message); ???????} ???????/// <summary> ???????/// 错误信息 ???????/// </summary> ???????/// <param name="source">source</param> ???????/// <param name="message">message</param> ???????public void Error(Type source, object message) ???????{ ???????????ILog logger = GetLogger(source); ???????????if (logger.IsErrorEnabled) ???????????{ ???????????????logger.Error(message); ???????????} ???????} ???????/// <summary> ???????/// 失败信息 ???????/// </summary> ???????/// <param name="source">source</param> ???????/// <param name="message">message</param> ???????public void Fatal(object source, object message) ???????{ ???????????Fatal(source.GetType(), message); ???????} ???????/// <summary> ???????/// 失败信息 ???????/// </summary> ???????/// <param name="source">source</param> ???????/// <param name="message">message</param> ???????public void Fatal(Type source, object message) ???????{ ???????????ILog logger = GetLogger(source); ???????????if (logger.IsFatalEnabled) ???????????{ ???????????????logger.Fatal(message); ???????????} ???????} ???????/* Log a message object and exception */ ???????/// <summary> ???????/// 调试信息 ???????/// </summary> ???????/// <param name="source">source</param> ???????/// <param name="message">message</param> ???????/// <param name="exception">ex</param> ???????public void Debug(object source, object message, Exception exception) ???????{ ???????????Debug(source.GetType(), message, exception); ???????} ???????/// <summary> ???????/// 调试信息 ???????/// </summary> ???????/// <param name="source">source</param> ???????/// <param name="message">message</param> ???????/// <param name="exception">ex</param> ???????public void Debug(Type source, object message, Exception exception) ???????{ ???????????GetLogger(source).Debug(message, exception); ???????} ???????/// <summary> ???????/// 关键信息 ???????/// </summary> ???????/// <param name="source">source</param> ???????/// <param name="message">message</param> ???????/// <param name="exception">ex</param> ???????public void Info(object source, object message, Exception exception) ???????{ ???????????Info(source.GetType(), message, exception); ???????} ???????/// <summary> ???????/// 关键信息 ???????/// </summary> ???????/// <param name="source">source</param> ???????/// <param name="message">message</param> ???????/// <param name="exception">ex</param> ???????public void Info(Type source, object message, Exception exception) ???????{ ???????????GetLogger(source).Info(message, exception); ???????} ???????/// <summary> ???????/// 警告信息 ???????/// </summary> ???????/// <param name="source">source</param> ???????/// <param name="message">message</param> ???????/// <param name="exception">ex</param> ???????public void Warn(object source, object message, Exception exception) ???????{ ???????????Warn(source.GetType(), message, exception); ???????} ???????/// <summary> ???????/// 警告信息 ???????/// </summary> ???????/// <param name="source">source</param> ???????/// <param name="message">message</param> ???????/// <param name="exception">ex</param> ???????public void Warn(Type source, object message, Exception exception) ???????{ ???????????GetLogger(source).Warn(message, exception); ???????} ???????/// <summary> ???????/// 错误信息 ???????/// </summary> ???????/// <param name="source">source</param> ???????/// <param name="message">message</param> ???????/// <param name="exception">ex</param> ???????public void Error(object source, object message, Exception exception) ???????{ ???????????Error(source.GetType(), message, exception); ???????} ???????/// <summary> ???????/// 错误信息 ???????/// </summary> ???????/// <param name="source">source</param> ???????/// <param name="message">message</param> ???????/// <param name="exception">ex</param> ???????public void Error(Type source, object message, Exception exception) ???????{ ???????????GetLogger(source).Error(message, exception); ???????} ???????/// <summary> ???????/// 失败信息 ???????/// </summary> ???????/// <param name="source">source</param> ???????/// <param name="message">message</param> ???????/// <param name="exception">ex</param> ???????public void Fatal(object source, object message, Exception exception) ???????{ ???????????Fatal(source.GetType(), message, exception); ???????} ???????/// <summary> ???????/// 失败信息 ???????/// </summary> ???????/// <param name="source">source</param> ???????/// <param name="message">message</param> ???????/// <param name="exception">ex</param> ???????public void Fatal(Type source, object message, Exception exception) ???????{ ???????????GetLogger(source).Fatal(message, exception); ???????} ???}}2、引用 nuget 包
这个时候，你会发现还有一个错误 ， 不过别慌，请往下看。
三、配置 LogManger 自启动
1、在启动文件中添加 Loger 日志仓库
这个具体深入的概念，我还在研究中，有时间补充下，这里大概了解用法以及概念，留一个坑
???????/// <summary> ???????/// log4net 仓储库 ???????/// </summary> ???????public static ILoggerRepository repository { get; set; }Repository可以说成基于一个log4net配置节创建的log4net容器，它根据log4net配置节的指示创建其他所有对象（Logger/Appender/Filter/Layout等等）并保有他们的实例，随时为你所用。
每个Repository都有自己唯一的名字，如root。
一般而言一个AppDomain(或者说一个进程)有一个Repository，该AppDomain下所有程序集Assembly都可以使用这个Repository。Repository需要实现ILoggerRepository，log4net中log4net.Repository.Hierarchy.Hierarchy就通过继承LoggerRepositorySkeleton实现了ILoggerRepository，它也是log4net中唯一实现ILoggerRepository的类。
2、在 Startup.cs 启动文件的 构造函数中，添加日志启动
//log4net repository = LogManager.CreateRepository("");//需要获取日志的仓库名，也就是你的当然项目名 //指定配置文件 XmlConfigurator.Configure(repository, new FileInfo("log4net.config"));//配置文件3、配置 log4net.config 文件
在 Blog.core 根目录下，添加Log4net.config
<?xml version="1.0" encoding="utf-8"?><configuration> ?<configSections> ???<section name="log4net" type="log4net.Config.Log4NetConfigurationSectionHandler, log4net"/> ?</configSections> ?<log4net> ???<!-- 将日志以回滚文件的形式写到文件中 --> ???<!-- 按日期切分日志文件，并将日期作为日志文件的名字 --> ???<appender name="RollingFileAppenderNameByDate" type="log4net.Appender.RollingFileAppender"> ?????<!-- 日志文件存放位置，可以为绝对路径也可以为相对路径 --> ?????<file value="C:\Logs\" /> ?????<!-- 将日志信息追加到已有的日志文件中--> ?????<appendToFile value="true" /> ?????<!-- 最小锁定模式，以允许多个进程可以写入同一个文件 --> ?????<lockingModel type="log4net.Appender.FileAppender+MinimalLock" /> ?????<!-- 指定按日期切分日志文件 --> ?????<rollingStyle value="Date" /> ?????<!-- 日志文件的命名规则 --> ?????<datePattern value=""UtilLogs_"yyyyMMdd".log"" /> ?????<!-- 当将日期作为日志文件的名字时，必须将staticLogFileName的值设置为false --> ?????<staticLogFileName value="false" /> ?????<!-- 日志显示模板 --> ?????<layout type="log4net.Layout.PatternLayout"> ???????<conversionPattern value="【异常时间】：%date %newline%message%newline--------------------------------------------------------------------%newline" /> ?????</layout> ???</appender> ???<root> ?????<!-- 控制级别，由低到高：ALL|DEBUG|INFO|WARN|ERROR|FATAL|OFF --> ?????<!-- 比如定义级别为INFO，则INFO级别向下的级别，比如DEBUG日志将不会被记录 --> ?????<!-- 如果没有定义LEVEL的值，则缺省为DEBUG --> ?????<level value="ALL" /> ?????<!-- 按日期切分日志文件，并将日期作为日志文件的名字 --> ?????<appender-ref ref="RollingFileAppenderNameByDate" /> ???</root> ?</log4net></configuration>
最终的结构是
这个时候，我们已经把日志添加好了，可以在任何需用用的地方去使用了，你会问了，不是全局么，总不能每个方法都写 try catch 吧，有想法，请往下看。
四、定义全局异常过滤器
1、日志接口进行注入
在 启动文件的 ConfigureServices方法中，添加服务注入
??//log日志注入 ??services.AddSingleton<ILoggerHelper, LogHelper>();
2、Blog.core 新建Filter 文件夹，添加GlobalExceptionFilter.cs
namespace Blog.Core.Filter{ ???/// <summary> ???/// 全局异常错误日志 ???/// </summary> ???public class GlobalExceptionsFilter : IExceptionFilter ???{ ???????private readonly IHostingEnvironment _env; ???????private readonly ILoggerHelper _loggerHelper; ???????public GlobalExceptionsFilter(IHostingEnvironment env, ILoggerHelper loggerHelper) ???????{ ???????????_env = env; ???????????_loggerHelper = loggerHelper; ???????} ???????public void OnException(ExceptionContext context) ???????{ ???????????var json = new JsonErrorResponse(); ???????????json.Message = context.Exception.Message;//错误信息 ???????????if (_env.IsDevelopment()) ???????????{ ???????????????json.DevelopmentMessage = context.Exception.StackTrace;//堆栈信息 ???????????} ???????????context.Result = new InternalServerErrorObjectResult(json); ???????????//采用log4net 进行错误日志记录 ???????????_loggerHelper.Error(json.Message, WriteLog(json.Message, context.Exception)); ???????} ???????/// <summary> ???????/// 自定义返回格式 ???????/// </summary> ???????/// <param name="throwMsg"></param> ???????/// <param name="ex"></param> ???????/// <returns></returns> ???????public string WriteLog(string throwMsg, Exception ex) ???????{ ???????????return string.Format("【自定义错误】：{0} \r\n【异常类型】：{1} \r\n【异常信息】：{2} \r\n【堆栈调用】：{3}", new object[] { throwMsg, ???????????????ex.GetType().Name, ex.Message, ex.StackTrace }); ???????} ???} ???public class InternalServerErrorObjectResult : ObjectResult ???{ ???????public InternalServerErrorObjectResult(object value) : base(value) ???????{ ???????????StatusCode = StatusCodes.Status500InternalServerError; ???????} ???} ???//返回错误信息 ???public class JsonErrorResponse ???{ ???????/// <summary> ???????/// 生产环境的消息 ???????/// </summary> ???????public string Message { get; set; } ???????/// <summary> ???????/// 开发环境的消息 ???????/// </summary> ???????public string DevelopmentMessage { get; set; } ???}}3、在启动服务中，注入全局异常
//注入全局异常捕获services.AddMvc(o =>{ ???o.Filters.Add(typeof(GlobalExceptionsFilter));}).SetCompatibilityVersion(CompatibilityVersion.Version_2_1);结构是这样的
4、自定义错误进行测试
我故意写错数据库连接字符串，看看 swagger 如何报错
看看日志是如何记录的
五、结语
今天是不定期更新系列，也是群里小伙伴提出来的想法，我自己简单搞搞，这里希望大家可以积极提意见哟，如果技术不错，我会把你的个人主页和Git放到文章中，也算是鼓励大家的一个方式了。
六、Github & Gitee
https://github.com/anjoy8/Blog.Core
https://gitee.com/laozhangIsPhi/Blog.Core
从壹开始前后端分离 [.netCore 不定期更新 ] 三十五║ 完美实现全局异常日志记录
原文地址：https://www.cnblogs.com/laozhang-is-phi/p/9855836.html