How can I include SessionID in log files using log4net in ASP.NET?

protected void Application_PostAcquireRequestState(object sender, EventArgs e)
{
    log4net.ThreadContext.Properties["SessionID"] = Session.SessionID;
}

protected void Application_PostAcquireRequestState(object sender, EventArgs e)
{
    if (Context.Handler is IRequiresSessionState)
    {
        log4net.ThreadContext.Properties["SessionId"] = Session.SessionID;
    }
}

private void AcquireRequestState(Object source, EventArgs e)
    {
        HttpApplication application = (HttpApplication)source;
        HttpContext context = application.Context;
        log4net.ThreadContext.Properties["SessionId"] = context.Session.SessionID;
     }

<appender name="rollingFile"
      type="log4net.Appender.RollingFileAppender,log4net" >
  <param name="AppendToFile" value="false" />
  <param name="RollingStyle" value="Date" />
  <param name="DatePattern" value="yyyy.MM.dd" />
  <param name="StaticLogFileName" value="true" />

  <param name="File" value="log.txt" />
  <layout type="log4net.Layout.PatternLayout,log4net">
    <param name="ConversionPattern"
      value="%property{SessionId} %d [%t] %-5p %c - %m%n" />
  </layout>
</appender>

<conversionPattern
    value="%date %-5level %logger ${COMPUTERNAME} [%property{SessionID}] - %message%newline" />

protected void Session_Start(object sender, EventArgs e)
{
    log4net.ThreadContext.Properties["SessionID"] = Session.SessionID;
    log4net.Config.XmlConfigurator.Configure();
}