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lang: ja-jp
breaks: true
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# `WinUI 3` で `log4net` を使用する 2022-11-22

普通に使えた。`MSIX` による `サイドローディング` パッケージ配布後でも普通に使える。

## csproj

<Project Sdk="Microsoft.NET.Sdk">
・・・
  <ItemGroup>
    <PackageReference Include="log4net" Version="2.0.15" />
  </ItemGroup>    
・・・
</Project>

## App.xaml.cs

[assembly: log4net.Config.XmlConfigurator(ConfigFile = "log4net.config", Watch = true)]

namespace WinUI3LogOutput;
public partial class App : Application
{
    public static ILog logger = LogManager.GetLogger(typeof(Program));
    public App()
    {
        this.InitializeComponent();
    }
    protected override void OnLaunched(Microsoft.UI.Xaml.LaunchActivatedEventArgs args)
    {
        m_window = new MainWindow();
        m_window.Activate();
    }

    private Window m_window;
}

## MainWindow.xaml.cs

namespace WinUI3LogOutput;

/// <summary>
/// An empty window that can be used on its own or navigated to within a Frame.
/// </summary>
public sealed partial class MainWindow : Window
{
    public MainWindow()
    {
        this.InitializeComponent();
    }

    private void myButton_Click(object sender, RoutedEventArgs e)
    {
        myButton.Content = "Clicked";

        App.logger.Debug("ログ出力のテスト");
    }
}

## log4net.config

<?xml version="1.0" encoding="utf-8" ?>
<configuration>

	<log4net>
		<appender name="RollingLogFileAppender" type="log4net.Appender.RollingFileAppender">
			<lockingModel type="log4net.Appender.FileAppender+MinimalLock" />
			<param name="File"               value="${TEMP}\${COMPUTERNAME}_XXXXXXXX"/>
			<param name="AppendToFile"       value="true"/>
			<param name="RollingStyle"       value="Composite"/>
			<param name="StaticLogFileName"  value="false"/>
			<param name="DatePattern"        value="&quot;_&quot;yyyyMMdd&quot;.log&quot;"/>
			<param name="MaxSizeRollBackups" value="100"/>
			<param name="MaximumFileSize"    value="50MB"/>
			<layout type="log4net.Layout.PatternLayout">
				<header type="log4net.Util.PatternString" value="[ task time = &quot;%date{HH:mm:ss,fff}&quot;]%newline"/>
				<footer type="log4net.Util.PatternString" value="[/task time = &quot;%date{HH:mm:ss,fff}&quot;]%newline"/>
				<param name="ConversionPattern" value="%d [%-2t] %-5p %m%n"/>
			</layout>
			<Encoding value="UTF-8"/>
		</appender>

		<appender name="BufferingForwardingAppender" type="log4net.Appender.BufferingForwardingAppender">
			<bufferSize value="512000" />
			<appender-ref ref="RollingLogFileAppender" />
			<!--
			<Fix value="All"/>
			<Fix value="NONE"/>
			<Fix value="Partial"/>
			<Fix value="463"/>
			-->
			<Fix value="463"/>
		</appender>

		<root>
			<!-- ログのレベルを指定 -->
			<!-- すべてのログレベルを出力 -->
			<!--
			<level value="ALL" />
			<level value="DEBUG" />
			<level value="INFO" />
			<level value="WARN" />
			<level value="ERROR" />
			<level value="FATAL" />
			-->
			<level value="ALL"/>
			<!-- どのログ出力先を使用するか -->
			<!--
			<appender-ref ref="RollingLogFileAppender"/>
			<appender-ref ref="BufferingForwardingAppender" />
			-->
			<appender-ref ref="RollingLogFileAppender"/>
		</root>

	</log4net>
</configuration>


## App.config でも対応可能

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

	<appSettings>
		<!-- log4net 内部のデバッグメッセージを出力 -->
		<add key="log4net.Internal.Debug" value="false" />
	</appSettings>

	<log4net>
		<appender name="RollingLogFileAppender" type="log4net.Appender.RollingFileAppender">
			<lockingModel type="log4net.Appender.FileAppender+MinimalLock" />
			<param name="File"               value="${TEMP}\${COMPUTERNAME}_XXXXXXXX"/>
			<param name="AppendToFile"       value="true"/>
			<param name="RollingStyle"       value="Composite"/>
			<param name="StaticLogFileName"  value="false"/>
			<param name="DatePattern"        value="&quot;_&quot;yyyyMMdd&quot;.log&quot;"/>
			<param name="MaxSizeRollBackups" value="100"/>
			<param name="MaximumFileSize"    value="50MB"/>
			<layout type="log4net.Layout.PatternLayout">
				<header type="log4net.Util.PatternString" value="[ task time = &quot;%date{HH:mm:ss,fff}&quot;]%newline"/>
				<footer type="log4net.Util.PatternString" value="[/task time = &quot;%date{HH:mm:ss,fff}&quot;]%newline"/>
				<param name="ConversionPattern" value="%d [%-2t] %-5p %m%n"/>
			</layout>
			<Encoding value="UTF-8"/>
		</appender>

		<appender name="BufferingForwardingAppender" type="log4net.Appender.BufferingForwardingAppender">
			<bufferSize value="512000" />
			<appender-ref ref="RollingLogFileAppender" />
			<!--
			<Fix value="All"/>
			<Fix value="NONE"/>
			<Fix value="Partial"/>
			<Fix value="463"/>
			-->
			<Fix value="463"/>
		</appender>

		<root>
			<!-- ログのレベルを指定 -->
			<!-- すべてのログレベルを出力 -->
			<!--
			<level value="ALL" />
			<level value="DEBUG" />
			<level value="INFO" />
			<level value="WARN" />
			<level value="ERROR" />
			<level value="FATAL" />
			-->
			<level value="ALL"/>
			<!-- どのログ出力先を使用するか -->
			<!--
			<appender-ref ref="RollingLogFileAppender"/>
			<appender-ref ref="BufferingForwardingAppender" />
			-->
			<appender-ref ref="RollingLogFileAppender"/>
		</root>

	</log4net>
</configuration>    

###### tags: `WinUI 3` `log4net` `MSIX` `ロギング`