咱們在編寫程序時，會在程序運行過程當中記錄一些日誌。log4net做爲一款經久耐用的日誌組件，值得咱們信賴。在中小型公司中，每每沒有專業的日誌服務器來處理應用程序產生的日誌，而格式化很差的日誌文件又爲上線後日志的統計、分析、查找形成了困難。html
Excel做爲一款經常使用的辦公軟件，用來處理一些中小數量級的數據仍是遊刃有餘的。若是log4net輸出的日誌可以直接導入Excel，那麼查詢和分析起來豈不是要快不少？服務器
咱們有不少方法能夠實現這個功能，csv的優點是其文件格式比較簡單，能夠用任意的文本編輯器打開，並且解析起來比較方便。效果以下：app
新建控制檯程序，引用log4net類庫這些步驟沒必要說，直接進入正題，咱們須要增長4個類文件 CsvTextWriter 、 NewFieldConverter 、 EndRowConverter 和 CsvPatternLayout。編輯器
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測試
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 }
在書寫 log4net 的配置文件時，只要將 appender 的 layout 設置爲 CoderBusy.Log4Net.Layout.CsvPatternLayout ，且設置好日誌頭，日誌格式便可。注意，header後須要編寫換行字符，%newfield表明字段分隔符，%endrow表明一行結束。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>
我爲初學者準備了一個log4net的配置文件。這個配置文件會將日誌在控制檯和csv文件中同時輸出，天天一個CSV文件（本地時間），且控制檯中，不一樣的日誌級別會有不一樣的顏色。 .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，測試一下功能。
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文件夾中，生成的csv文件內容以下：
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=
",""
輸出字段被使用雙引號包裹，且消息體中的雙引號被重複輸出。這樣的結果代表咱們的程序是正常的。本文的代碼能夠在 http://pan.baidu.com/s/1hr4EOPu 下載，謝謝閱讀，並祝你成功。