Log4net xml输出

Question

我想完全控制log4net xml输出.

如何自定义输出模板？

Answer 1

正如MrPeregrination 所建议的,您需要编写一个派生自XmlLayoutBase的类,重写FormatXml方法并指示您的appender将其用作布局:

class Program
{
    static void Main(string[] args)
    {
        XmlConfigurator.Configure();
        ILog log = log4net.LogManager.GetLogger(typeof(Program));
        log.Debug("Hello world");
    }
}

public class MyXmlLayout : XmlLayoutBase
{
    protected override void FormatXml(XmlWriter writer, LoggingEvent loggingEvent)
    {
        writer.WriteStartElement("LogEntry");
        writer.WriteStartElement("Message");
        writer.WriteString(loggingEvent.RenderedMessage);
        writer.WriteEndElement();
        writer.WriteEndElement();
    }
}

在app.config中输入:

<?xml version="1.0" encoding="utf-8" ?>
<configuration>
  <configSections>
    <section name="log4net" type="log4net.Config.Log4NetConfigurationSectionHandler,log4net"/>
  </configSections>

  <log4net>
    <appender name="LogFileAppender" type="log4net.Appender.RollingFileAppender" >
      <param name="File" value="log.txt" />
      <param name="AppendToFile" value="true" />
      <rollingStyle value="Size" />
      <maxSizeRollBackups value="10" />
      <maximumFileSize value="10MB" />
      <staticLogFileName value="true" />
      <layout type="MyNamespace.MyXmlLayout" />
    </appender>

    <root>
      <level value="DEBUG" />
      <appender-ref ref="LogFileAppender" />
    </root>
  </log4net>
</configuration>

这将在您的日志文件中生成这样的条目:

<LogEntry><Message>Hello world</Message></LogEntry>

Answer 2

在Darin的答案中，在log4net 2.0.8中，我不得不稍微更改了布局：

<layout type="MyNamespace.MyClass, MyNamespace"/>

我在这里找到了这个http://www.codewrecks.com/blog/index.php/2008/04/29/writing-a-custom-formatter-for-log4net/