/// <summary>        /// Static constructor that initializes logging by reading         /// settings from the application configuration file.        /// </summary>        /// <remarks>        /// <para>        /// The <c>log4net.Internal.Debug</c> application setting        /// controls internal debugging. This setting should be set        /// to <c>true</c> to enable debugging.        /// </para>        /// <para>        /// The <c>log4net.Internal.Quiet</c> application setting        /// suppresses all internal logging including error messages.         /// This setting should be set to <c>true</c> to enable message        /// suppression.        /// </para>        /// </remarks>        static LogLog()        {#if !NETCF            try            {                InternalDebugging = OptionConverter.ToBoolean(SystemInfo.GetAppSetting("log4net.Internal.Debug"), false);                QuietMode = OptionConverter.ToBoolean(SystemInfo.GetAppSetting("log4net.Internal.Quiet"), false);                EmitInternalMessages = OptionConverter.ToBoolean(SystemInfo.GetAppSetting("log4net.Internal.Emit"), true);            }            catch(Exception ex)            {                // If an exception is thrown here then it looks like the config file does not                // parse correctly.                //                // We will leave debug OFF and print an Error message                Error(typeof(LogLog), "Exception while reading ConfigurationSettings. Check your .config file is well formed XML.", ex);            }#endif        }

    #region Public Static Properties        /// <summary>        /// Gets or sets a value indicating whether log4net internal logging        /// is enabled or disabled.        /// </summary>        /// <value>        /// <c>true</c> if log4net internal logging is enabled, otherwise         /// <c>false</c>.        /// </value>        /// <remarks>        /// <para>        /// When set to <c>true</c>, internal debug level logging will be         /// displayed.        /// </para>        /// <para>        /// This value can be set by setting the application setting         /// <c>log4net.Internal.Debug</c> in the application configuration        /// file.        /// </para>        /// <para>        /// The default value is <c>false</c>, i.e. debugging is        /// disabled.        /// </para>        /// </remarks>        /// <example>        /// <para>        /// The following example enables internal debugging using the         /// application configuration file :        /// </para>        /// <code lang="XML" escaped="true">        /// <configuration>        ///        <appSettings>        ///            <add key="log4net.Internal.Debug" value="http://www.mamicode.com/true" />        ///        </appSettings>        /// </configuration>        /// </code>        /// </example>        public static bool InternalDebugging        {            get { return s_debugEnabled; }            set { s_debugEnabled = value; }        }        /// <summary>        /// Gets or sets a value indicating whether log4net should generate no output        /// from internal logging, not even for errors.         /// </summary>        /// <value>        /// <c>true</c> if log4net should generate no output at all from internal         /// logging, otherwise <c>false</c>.        /// </value>        /// <remarks>        /// <para>        /// When set to <c>true</c> will cause internal logging at all levels to be         /// suppressed. This means that no warning or error reports will be logged.         /// This option overrides the <see cref="InternalDebugging"/> setting and         /// disables all debug also.        /// </para>        /// <para>This value can be set by setting the application setting        /// <c>log4net.Internal.Quiet</c> in the application configuration file.        /// </para>        /// <para>        /// The default value is <c>false</c>, i.e. internal logging is not        /// disabled.        /// </para>        /// </remarks>        /// <example>        /// The following example disables internal logging using the         /// application configuration file :        /// <code lang="XML" escaped="true">        /// <configuration>        ///        <appSettings>        ///            <add key="log4net.Internal.Quiet" value="http://www.mamicode.com/true" />        ///        </appSettings>        /// </configuration>        /// </code>        /// </example>        public static bool QuietMode        {            get { return s_quietMode; }            set { s_quietMode = value; }        }        /// <summary>        ///         /// </summary>        public static bool EmitInternalMessages        {            get { return s_emitInternalMessages; }            set { s_emitInternalMessages = value; }        }        #endregion Public Static Properties

 /// <summary>        /// Raises the LogReceived event when an internal messages is received.        /// </summary>        /// <param name="source"></param>        /// <param name="prefix"></param>        /// <param name="message"></param>        /// <param name="exception"></param>        public static void OnLogReceived(Type source, string prefix, string message, Exception exception)        {            if (LogReceived != null)            {                LogReceived(null, new LogReceivedEventArgs(new LogLog(source, prefix, message, exception)));            }        }        /// <summary>        /// Test if LogLog.Debug is enabled for output.        /// </summary>        /// <value>        /// <c>true</c> if Debug is enabled        /// </value>        /// <remarks>        /// <para>        /// Test if LogLog.Debug is enabled for output.        /// </para>        /// </remarks>        public static bool IsDebugEnabled        {            get { return s_debugEnabled && !s_quietMode; }        }        /// <summary>        /// Writes log4net internal debug messages to the         /// standard output stream.        /// </summary>        /// <param name="source"></param>        /// <param name="message">The message to log.</param>        /// <remarks>        /// <para>        ///    All internal debug messages are prepended with         ///    the string "log4net: ".        /// </para>        /// </remarks>        public static void Debug(Type source, string message)         {            if (IsDebugEnabled)             {                if (EmitInternalMessages)                {                    EmitOutLine(PREFIX + message);                }                OnLogReceived(source, PREFIX, message, null);            }        }        /// <summary>        /// Writes log4net internal debug messages to the         /// standard output stream.        /// </summary>        /// <param name="source">The Type that generated this message.</param>        /// <param name="message">The message to log.</param>        /// <param name="exception">An exception to log.</param>        /// <remarks>        /// <para>        ///    All internal debug messages are prepended with         ///    the string "log4net: ".        /// </para>        /// </remarks>        public static void Debug(Type source, string message, Exception exception)         {            if (IsDebugEnabled)             {                if (EmitInternalMessages)                {                    EmitOutLine(PREFIX + message);                    if (exception != null)                    {                        EmitOutLine(exception.ToString());                    }                }                OnLogReceived(source, PREFIX, message, exception);            }        }          /// <summary>        /// Test if LogLog.Warn is enabled for output.        /// </summary>        /// <value>        /// <c>true</c> if Warn is enabled        /// </value>        /// <remarks>        /// <para>        /// Test if LogLog.Warn is enabled for output.        /// </para>        /// </remarks>        public static bool IsWarnEnabled        {            get { return !s_quietMode; }        }        /// <summary>        /// Writes log4net internal warning messages to the         /// standard error stream.        /// </summary>        /// <param name="source">The Type that generated this message.</param>        /// <param name="message">The message to log.</param>        /// <remarks>        /// <para>        ///    All internal warning messages are prepended with         ///    the string "log4net:WARN ".        /// </para>        /// </remarks>        public static void Warn(Type source, string message)         {            if (IsWarnEnabled)            {                if (EmitInternalMessages)                {                    EmitErrorLine(WARN_PREFIX + message);                }                OnLogReceived(source, WARN_PREFIX, message, null);            }        }