咱们在编写程序时，会在程序运行过程当中记录一些日志。log4net做为一款经久耐用的日志组件，值得咱们信赖。在中小型公司中，每每没有专业的日志服务器来处理应用程序产生的日志，而格式化很差的日志文件又为上线后日志的统计、分析、查找形成了困难。html
Excel做为一款经常使用的办公软件，用来处理一些中小数量级的数据仍是游刃有余的。若是log4net输出的日志可以直接导入Excel，那么查询和分析起来岂不是要快不少？服务器
咱们有不少方法能够实现这个功能，csv的优点是其文件格式比较简单，能够用任意的文本编辑器打开，并且解析起来比较方便。效果以下：app
新建控制台程序，引用log4net类库这些步骤没必要说，直接进入正题，咱们须要增长4个类文件 CsvTextWriter 、 NewFieldConverter 、 EndRowConverter 和 CsvPatternLayout。编辑器
CsvTextWriter.cside
1 using System.IO; 2 using System.Text; 3 4 namespace CoderBusy.Log4Net.Layout 5 { 6 public class CsvTextWriter : TextWriter 7 { 8 private readonly TextWriter _textWriter; 9 10 public CsvTextWriter(TextWriter textWriter) 11 { 12 _textWriter = textWriter; 13 } 14 15 public override Encoding Encoding => _textWriter.Encoding; 16 17 public override void Write(char value) 18 { 19 _textWriter.Write(value); 20 if (value == '"') 21 _textWriter.Write(value); 22 } 23 24 public void WriteQuote() 25 { 26 _textWriter.Write('"'); 27 } 28 } 29 }
NewFieldConverter.cspost
1 using System.IO; 2 using log4net.Util; 3 4 namespace CoderBusy.Log4Net.Layout 5 { 6 public class NewFieldConverter : PatternConverter 7 { 8 protected override void Convert(TextWriter writer, object state) 9 { 10 var ctw = writer as CsvTextWriter; 11 ctw?.WriteQuote(); 12 13 writer.Write(','); 14 15 ctw?.WriteQuote(); 16 } 17 } 18 }
EndRowConverter.cs测试
1 using System.IO; 2 using log4net.Util; 3 4 namespace CoderBusy.Log4Net.Layout 5 { 6 public class EndRowConverter : PatternConverter 7 { 8 protected override void Convert(TextWriter writer, object state) 9 { 10 var ctw = writer as CsvTextWriter; 11 12 ctw?.WriteQuote(); 13 14 writer.WriteLine(); 15 } 16 } 17 }
CsvPatternLayout.csurl
1 using System.IO; 2 using log4net.Core; 3 using log4net.Layout; 4 5 namespace CoderBusy.Log4Net.Layout 6 { 7 public class CsvPatternLayout : PatternLayout 8 { 9 public override void ActivateOptions() 10 { 11 AddConverter("newfield", typeof(NewFieldConverter)); 12 AddConverter("endrow", typeof(EndRowConverter)); 13 base.ActivateOptions(); 14 } 15 16 public override void Format(TextWriter writer, LoggingEvent loggingEvent) 17 { 18 var ctw = new CsvTextWriter(writer); 19 ctw.WriteQuote(); 20 base.Format(ctw, loggingEvent); 21 } 22 } 23 }
在书写 log4net 的配置文件时，只要将 appender 的 layout 设置为 CoderBusy.Log4Net.Layout.CsvPatternLayout ，且设置好日志头，日志格式便可。注意，header后须要编写换行字符，%newfield表明字段分隔符，%endrow表明一行结束。spa
<layout type="CoderBusy.Log4Net.Layout.CsvPatternLayout,CoderBusy.Log4Net"> <header value="Time,Thread,Level,Logger,Message,Exception " /> <conversionPattern value="%date{yyyy-MM-dd HH:mm:ss}%newfield%thread%newfield%level%newfield%logger%newfield%message%newfield%exception%endrow" /> </layout>
我为初学者准备了一个log4net的配置文件。这个配置文件会将日志在控制台和csv文件中同时输出，天天一个CSV文件（本地时间），且控制台中，不一样的日志级别会有不一样的颜色。 .net
1 <?xml version="1.0" encoding="utf-8"?> 2 3 <configuration> 4 <configSections> 5 <section name="log4net" type="log4net.Config.Log4NetConfigurationSectionHandler, log4net" /> 6 </configSections> 7 <log4net xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"> 8 <appender name="RollingLogFileAppender" type="log4net.Appender.RollingFileAppender"> 9 <param name="File" value="Logs/" /> 10 <param name="AppendToFile" value="True" /> 11 <param name="MaxSizeRollBackups" value="10" /> 12 <param name="StaticLogFileName" value="false" /> 13 <param name="DatePattern" value="yyyy-MM-dd".csv"" /> 14 <param name="RollingStyle" value="Date" /> 15 <layout type="CoderBusy.Log4Net.Layout.CsvPatternLayout,CoderBusy.Log4Net"> 16 <header value="Time,Thread,Level,Logger,Message,Exception " /> 17 <conversionPattern 18 value="%date{yyyy-MM-dd HH:mm:ss}%newfield%thread%newfield%level%newfield%logger%newfield%message%newfield%exception%endrow" /> 19 </layout> 20 </appender> 21 22 <appender name="ColoredConsoleAppender" type="log4net.Appender.ColoredConsoleAppender"> 23 <mapping> 24 <level value="ERROR" /> 25 <foreColor value="Red" /> 26 </mapping> 27 <mapping> 28 <level value="INFO" /> 29 <foreColor value="Green" /> 30 </mapping> 31 32 <layout type="log4net.Layout.PatternLayout"> 33 <conversionPattern value="# %date{HH:mm:ss} [%thread] %-5level %logger #%newline%message%newline" /> 34 </layout> 35 <filter type="log4net.Filter.LevelRangeFilter"> 36 <param name="LevelMin" value="DEBUG" /> 37 <param name="LevelMax" value="FATAL" /> 38 </filter> 39 </appender> 40 41 <root> 42 <!-- OFF < FATAL < ERROR < WARN < INFO < DEBUG < ALL --> 43 <level value="ALL" /> 44 <appender-ref ref="RollingLogFileAppender" /> 45 <appender-ref ref="ColoredConsoleAppender" /> 46 </root> 47 </log4net> 48 </configuration>
配合以上配置，测试一下功能。
1 using System; 2 using log4net; 3 using log4net.Config; 4 5 [assembly: XmlConfigurator(ConfigFile = "log4net.config")] 6 7 namespace CoderBusy.Log4Net.Tests 8 { 9 internal class Program 10 { 11 public static void Main(string[] args) 12 { 13 var log = LogManager.GetLogger("Default"); 14 log.Debug("Message", new Exception("Test Exception")); 15 log.Info("Hello World."); 16 log.WarnFormat("A={0} B={1}", "\"123123", Environment.NewLine); 17 Console.ReadLine(); 18 } 19 } 20 }
Logs文件夹中，生成的csv文件内容以下：
Time,Thread,Level,Logger,Message,Exception
"2016-08-25 23:13:19","9","DEBUG","Default","Message","System.Exception: Test Exception
"
"2016-08-25 23:13:19","9","INFO","Default","Hello World.",""
"2016-08-25 23:13:19","9","WARN","Default","A=""123123 B=
",""
输出字段被使用双引号包裹，且消息体中的双引号被重复输出。这样的结果代表咱们的程序是正常的。本文的代码能够在 http://pan.baidu.com/s/1hr4EOPu 下载，谢谢阅读，并祝你成功。