C# log4net日志使用

第一步：新增帮助类库，即动态库，具体实现如下

using log4net;
using log4net.Appender;
using log4net.Config;
using log4net.Layout;
using log4net.Repository.Hierarchy;
using System;
using System.Data;
using System.Text;

namespace KUN.Common
{
    public class LogHelper
    {
        #region 变量定义
        //定义信息的二次处理
        public static event Action<string> OutputMessage;
        //ILog对象
        private static readonly ILog log = LogManager.GetLogger(System.Reflection.MethodBase.GetCurrentMethod().DeclaringType);
        //记录异常日志数据库连接字符串
        private const string _ConnectionString = @"data source=your server;initial catalog=your db;integrated security=false;persist security info=True;User ID=sa;Password=1111";
        //信息模板
        private const string _ConversionPattern = "%n【记录时间】%date%n【描述】%message%n";
        #endregion

        #region 定义信息二次处理方式
        private static void HandMessage(object Msg)
        {
            //if (OutputMessage != null)
            //{
            //    OutputMessage(Msg.ToString());
            //}
        }
        private static void HandMessage(object Msg, Exception ex)
        {
            if (OutputMessage != null)
            {
                OutputMessage(string.Format("{0}:{1}", Msg.ToString(), ex.ToString()));
            }
        }
        private static void HandMessage(string format, params object[] args)
        {
            if (OutputMessage != null)
            {
                OutputMessage(string.Format(format, args));
            }
        }
        #endregion

        #region 封装Log4net
        public static void Debug(object message)
        {
            HandMessage(message);
            if (log.IsDebugEnabled)
            {
                log.Debug(message);
            }
        }
        public static void Debug(object message, Exception ex)
        {
            HandMessage(message, ex);
            if (log.IsDebugEnabled)
            {
                log.Debug(message, ex);
            }
        }
        public static void DebugFormat(string format, params object[] args)
        {
            HandMessage(format, args);
            if (log.IsDebugEnabled)
            {
                log.DebugFormat(format, args);
            }
        }
        public static void Error(object message)
        {
            HandMessage(message);
            if (log.IsErrorEnabled)
            {
                log.Error(message);
            }
        }
        public static void Error(object message, Exception ex)
        {
            HandMessage(message, ex);
            if (log.IsErrorEnabled)
            {
                log.Error(message, ex);
            }
        }
        public static void ErrorFormat(string format, params object[] args)
        {
            HandMessage(format, args);
            if (log.IsErrorEnabled)
            {
                log.ErrorFormat(format, args);
            }
        }
        public static void Fatal(object message)
        {
            HandMessage(message);
            if (log.IsFatalEnabled)
            {
                log.Fatal(message);
            }
        }
        public static void Fatal(object message, Exception ex)
        {
            HandMessage(message, ex);
            if (log.IsFatalEnabled)
            {
                log.Fatal(message, ex);
            }
        }
        public static void FatalFormat(string format, params object[] args)
        {
            HandMessage(format, args);
            if (log.IsFatalEnabled)
            {
                log.FatalFormat(format, args);
            }
        }
        public static void Info(object message)
        {
            HandMessage(message);
            if (log.IsInfoEnabled)
            {
                log.Info(message);
            }
        }
        public static void Info(object message, Exception ex)
        {
            HandMessage(message, ex);
            if (log.IsInfoEnabled)
            {
                log.Info(message, ex);
            }
        }
        public static void InfoFormat(string format, params object[] args)
        {
            HandMessage(format, args);
            if (log.IsInfoEnabled)
            {
                log.InfoFormat(format, args);
            }
        }
        public static void Warn(object message)
        {
            HandMessage(message);
            if (log.IsWarnEnabled)
            {
                log.Warn(message);
            }
        }
        public static void Warn(object message, Exception ex)
        {
            HandMessage(message, ex);
            if (log.IsWarnEnabled)
            {
                log.Warn(message, ex);
            }
        }
        public static void WarnFormat(string format, params object[] args)
        {
            HandMessage(format, args);
            if (log.IsWarnEnabled)
            {
                log.WarnFormat(format, args);
            }
        }
        #endregion

        #region 手动加载配置
        public static void LoadADONetAppender()
        {
            Hierarchy hier = LogManager.GetLoggerRepository() as log4net.Repository.Hierarchy.Hierarchy;
            if (hier != null)
            {
                log4net.Appender.AdoNetAppender appender = new log4net.Appender.AdoNetAppender();
                appender.Name = "AdoNetAppender";
                appender.CommandType = CommandType.Text;
                appender.BufferSize = 1;
                appender.ConnectionType = "System.Data.SqlClient.SqlConnection, System.Data, Version=1.0.3300.0, Culture=neutral, PublicKeyToken=b77a5c561934e089";
                appender.ConnectionString = _ConnectionString;
                appender.CommandText = @"INSERT INTO Log ([Date],[Thread],[Level],[Logger],[Message],[Exception]) VALUES (@log_date, @thread, @log_level, @logger, @message, @exception)";
                appender.AddParameter(new AdoNetAppenderParameter { ParameterName = "@log_date", DbType = System.Data.DbType.DateTime, Layout = new log4net.Layout.RawTimeStampLayout() });
                appender.AddParameter(new AdoNetAppenderParameter { ParameterName = "@thread", DbType = System.Data.DbType.String, Size = 255, Layout = new Layout2RawLayoutAdapter(new PatternLayout("%thread")) });
                appender.AddParameter(new AdoNetAppenderParameter { ParameterName = "@log_level", DbType = System.Data.DbType.String, Size = 50, Layout = new Layout2RawLayoutAdapter(new PatternLayout("%level")) });
                appender.AddParameter(new AdoNetAppenderParameter { ParameterName = "@logger", DbType = System.Data.DbType.String, Size = 255, Layout = new Layout2RawLayoutAdapter(new PatternLayout("%logger")) });
                appender.AddParameter(new AdoNetAppenderParameter { ParameterName = "@message", DbType = System.Data.DbType.String, Size = 4000, Layout = new Layout2RawLayoutAdapter(new PatternLayout("%message")) });
                appender.AddParameter(new AdoNetAppenderParameter { ParameterName = "@exception", DbType = System.Data.DbType.String, Size = 4000, Layout = new Layout2RawLayoutAdapter(new ExceptionLayout()) });
                appender.ActivateOptions();
                BasicConfigurator.Configure(appender);
            }
        }

        public static void LoadFileAppender()
        {
            FileAppender appender = new FileAppender();
            appender.Name = "FileAppender";
            appender.File = "error.log";
            appender.AppendToFile = true;

            PatternLayout patternLayout = new PatternLayout();
            patternLayout.ConversionPattern = _ConversionPattern;
            patternLayout.ActivateOptions();
            appender.Layout = patternLayout;

            //选择UTF8编码，确保中文不乱码。
            appender.Encoding = Encoding.UTF8;

            appender.ActivateOptions();
            BasicConfigurator.Configure(appender);

        }

        public static void LoadRollingFileAppender()
        {
            RollingFileAppender appender = new RollingFileAppender();
            appender.AppendToFile = true;
            appender.Name = "RollingFileAppender";
            appender.DatePattern = "yyyy-MM-dd HH'时.log'";
            appender.File = "Logs/";
            appender.AppendToFile = true;
            appender.RollingStyle = RollingFileAppender.RollingMode.Composite;
            appender.MaximumFileSize = "500kb";
            appender.MaxSizeRollBackups = 10;
            appender.StaticLogFileName = false;


            PatternLayout patternLayout = new PatternLayout();
            patternLayout.ConversionPattern = _ConversionPattern;
            patternLayout.ActivateOptions();
            appender.Layout = patternLayout;

            //选择UTF8编码，确保中文不乱码。
            appender.Encoding = Encoding.UTF8;

            appender.ActivateOptions();
            BasicConfigurator.Configure(appender);
        }

        public static void LoadConsoleAppender()
        {
            ConsoleAppender appender = new ConsoleAppender();
            appender.Name = "ConsoleAppender";

            PatternLayout patternLayout = new PatternLayout();
            patternLayout.ConversionPattern = _ConversionPattern;
            patternLayout.ActivateOptions();
            appender.Layout = patternLayout;

            appender.ActivateOptions();
            BasicConfigurator.Configure(appender);
        }

        public static void LoadTraceAppender()
        {
            TraceAppender appender = new TraceAppender();
            appender.Name = "TraceAppender";

            PatternLayout patternLayout = new PatternLayout();
            patternLayout.ConversionPattern = _ConversionPattern;
            patternLayout.ActivateOptions();
            appender.Layout = patternLayout;

            appender.ActivateOptions();
            BasicConfigurator.Configure(appender);
        }

        #endregion

        #region 定义常规应用程序中未处理的异常信息记录方式
        public static void LoadUnhandledException()
        {
            AppDomain.CurrentDomain.UnhandledException += new UnhandledExceptionEventHandler((sender, e) =>
            {
                log.Fatal("未处理的异常", e.ExceptionObject as Exception);
            });
        }
        #endregion
    }
}

第二步：nuget安装log4net,略

第三步：配置文件复制到项目位置，略，同时设置属性为，始终复制+内容

log4net.config，内容如下

<?xml version="1.0" encoding="utf-8" ?>
<configuration>
  <!-- This section contains the log4net configuration settings -->
  <log4net>
    <appender name="ConsoleAppender" type="log4net.Appender.ConsoleAppender">
      <layout type="log4net.Layout.PatternLayout" value="%date [%thread] %-5level %logger - %message%newline" />
    </appender>

    <appender name="FileAppender" type="log4net.Appender.FileAppender">
      <file value="log-file.log" />
      <appendToFile value="true" />
      <layout type="log4net.Layout.PatternLayout">
        <conversionPattern value="%date [%thread] %-5level %logger [%property{NDC}] - %message%newline" />
      </layout>
    </appender>

    <appender name="RollingLogFileAppender" type="log4net.Appender.RollingFileAppender">
      <file value="Logs/" />
      <appendToFile value="true" />
      <rollingStyle value="Composite" />
      <staticLogFileName value="false" />
      <datePattern value="yyyyMMdd'.log'" />
      <maxSizeRollBackups value="10" />
      <maximumFileSize value="1MB" />
      <layout type="log4net.Layout.PatternLayout">
        <conversionPattern value="%date [%thread] %-5level %logger [%property{NDC}] - %message%newline" />
      </layout>
    </appender>

    <!-- Setup the root category, add the appenders and set the default level -->
    <root>
      <level value="ALL" />
      <appender-ref ref="RollingLogFileAppender" />
    </root>

  </log4net>
</configuration>

第四步：应用项目中，注册使用，如下所示：

using log4net.Config;
using log4net.Repository;
using System;
using System.IO;
using System.Windows.Forms;

namespace Demo
{
    static class Program
    {
        /// <summary>
        /// ILoggerRepository repository
        /// </summary>
        public static ILoggerRepository repository { get; set; }
        /// <summary>
        /// 应用程序的主入口点。
        /// </summary>
        [STAThread]
        static void Main()
        {
            Application.EnableVisualStyles();
            Application.SetCompatibleTextRenderingDefault(false);

            //加log4日志
            repository = log4net.LogManager.GetRepository();
            XmlConfigurator.Configure(repository, new FileInfo("log4net.config"));

            Application.Run(new Form1());
        }
    }
}

第五步：测试使用，如下，详细略

 private void btnLogTest_Click(object sender, EventArgs e)
        {
            LogHelper.ErrorFormat("log4net-{0}", "日志测试一把");
        }