Log4Net使用详解

说明自从上次在2008年在博客上发表过有关log4net的用法介绍文章之后（网址：http://blog.csdn.net/zhoufoxcn/archive/2008/03/26/2220533.aspx），有不少朋友在博文下留言询问一些细节，现在就一些比较普遍的问题做一些稍微深入的解答，希望大家满意。
首先说明一点的是，log4net解决的问题是提供一个记录日志的框架，它提供了向多种目标写入的实现，比如利用log4net可以方便地将日志信息记录到文件、控制台、Windows事件日志和数据库（包括MS SQL Server, Access, Oracle9i,Oracle8i,DB2,SQLite）中，一般来说我们只需要提供一个描述性的字符串，然后log4net就会自动提供有关运行时的一些信息。
Log4Net的版本仍是1.2.10（2008年我写博文的时候也是这个版本），有.NET1.0和.NET1.1和.NET2.0版本，如果有正在使用高于.NET2.0开发的也不用担心，可以直接引用这个类库，像在.NET2.0中开发一样，它的网址是：http://logging.apache.org/log4net/
关于在Web中支持的问题
在我们开发项目时都会使用到config文件，可以在config文件中配置log4net。这一点Web项目和WinForm项目都是一样的。需要注意的是，因为在Web项目中一般以较低权限的角色来运行Web项目的，所以在使用文件型日志时要注意不要放在本项目根文件夹之外。
在config文件中的配置

要使用log4net，首先要在config文件的<configSections>节点中增加配置（如果没有这个节点请手动增加），如下：

[xhtml] view plaincopyprint?

<configSections>

<section name="log4net" type="System.Configuration.IgnoreSectionHandler"/>

</configSections>

<appender name="AdoNetAppender_Oracle" type="log4net.Appender.AdoNetAppender">

<connectionType value="System.Data.OracleClient.OracleConnection, System.Data.OracleClient, Version=1.0.3300.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" />

<connectionString value="data source=[mydatabase];User ID=[user];Password=[password]" />

<commandText value="INSERT INTO Log (Datetime,Thread,Log_Level,Logger,Message) VALUES (:log_date, :thread, :log_level, :logger, :message)" />

<bufferSize value="128" />

<parameter>

<parameterName value=":log_date" />

<dbType value="DateTime" />

<layout type="log4net.Layout.RawTimeStampLayout" />

</parameter>

<parameter>

<parameterName value=":thread" />

<dbType value="String" />

<size value="255" />

<layout type="log4net.Layout.PatternLayout">

<conversionPattern value="%thread" />

</layout>

</parameter>

<parameter>

<parameterName value=":log_level" />

<dbType value="String" />

<size value="50" />

<layout type="log4net.Layout.PatternLayout">

<conversionPattern value="%level" />

</layout>

</parameter>

<parameter>

<parameterName value=":logger" />

<dbType value="String" />

<size value="255" />

<layout type="log4net.Layout.PatternLayout">

<conversionPattern value="%logger" />

</layout>

</parameter>

<parameter>

<parameterName value=":message" />

<dbType value="String" />

<size value="4000" />

<layout type="log4net.Layout.PatternLayout">

<conversionPattern value="%message" />

</layout>

</parameter>

</appender>

<appender name="AdoNetAppender_Oracle" type="log4net.Appender.AdoNetAppender">
<connectionType value="System.Data.OracleClient.OracleConnection, System.Data.OracleClient, Version=1.0.3300.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" />
<connectionString value="data source=[mydatabase];User ID=[user];Password=[password]" />
<commandText value="INSERT INTO Log (Datetime,Thread,Log_Level,Logger,Message) VALUES (:log_date, :thread, :log_level, :logger, :message)" />
<bufferSize value="128" />
<parameter>
<parameterName value=":log_date" />
<dbType value="DateTime" />
<layout type="log4net.Layout.RawTimeStampLayout" />
</parameter>
<parameter>
<parameterName value=":thread" />
<dbType value="String" />
<size value="255" />
<layout type="log4net.Layout.PatternLayout">
<conversionPattern value="%thread" />
</layout>
</parameter>
<parameter>
<parameterName value=":log_level" />
<dbType value="String" />
<size value="50" />
<layout type="log4net.Layout.PatternLayout">
<conversionPattern value="%level" />
</layout>
</parameter>
<parameter>
<parameterName value=":logger" />
<dbType value="String" />
<size value="255" />
<layout type="log4net.Layout.PatternLayout">
<conversionPattern value="%logger" />
</layout>
</parameter>
<parameter>
<parameterName value=":message" />
<dbType value="String" />
<size value="4000" />
<layout type="log4net.Layout.PatternLayout">
<conversionPattern value="%message" />
</layout>
</parameter>
</appender>

当然从上面的配置中的SQL语句中可以看得出这个表的参数，日志表的创建语句如下：

create table log (

Datetime timestamp(3),

Thread varchar2(255),

Log_Level varchar2(255),

Logger varchar2(255),

Message varchar2(4000)

);

CREATE TABLE Log (

LogId        INTEGER PRIMARY KEY,

Date        DATETIME NOT NULL,

Level        VARCHAR(50) NOT NULL,

Logger        VARCHAR(255) NOT NULL,

Source        VARCHAR(255) NOT NULL,

Message        TEXT DEFAULT NULL

);

CREATE TABLE Log (
LogId        INTEGER PRIMARY KEY,
Date        DATETIME NOT NULL,
Level        VARCHAR(50) NOT NULL,
Logger        VARCHAR(255) NOT NULL,
Source        VARCHAR(255) NOT NULL,
Message        TEXT DEFAULT NULL
);

增加的< appender>节点配置如下：

<appender name="AdoNetAppender_SQLite" type="log4net.Appender.AdoNetAppender">

<bufferSize value="100" />

<connectionType value="System.Data.SQLite.SQLiteConnection, System.Data.SQLite, Version=1.0.66.0, Culture=neutral" />

<!--SQLite连接字符串-->

<connectionString value="Data Source=c://log4net.db;Version=3;" />

<commandText value="INSERT INTO Log (Date, Level, Logger,Source, Message) VALUES (@Date, @Level, @Logger, @Source, @Message)" />

<parameter>

<parameterName value="@Date" />

<dbType value="DateTime" />

<layout type="log4net.Layout.RawTimeStampLayout" />

</parameter>

<parameter>

<parameterName value="@Level" />

<dbType value="String" />

<layout type="log4net.Layout.PatternLayout">

<conversionPattern value="%level" />

</layout>

</parameter>

<parameter>

<parameterName value="@Logger" />

<dbType value="String" />

<layout type="log4net.Layout.PatternLayout">

<conversionPattern value="%logger" />

</layout>

</parameter>

<parameter>

<parameterName value="@Source" />

<dbType value="String" />

<layout type="log4net.Layout.PatternLayout">

<conversionPattern value="%file:%line" />

</layout>

</parameter>

<parameter>

<parameterName value="@Message" />

<dbType value="String" />

<layout type="log4net.Layout.PatternLayout">

<conversionPattern value="%message" />

</layout>

</parameter>

</appender>

<appender name="RollingFileAppender" type="log4net.Appender.RollingFileAppender">

<file value="RollingFileAppender_log.txt" />

<appendToFile value="true" />

<rollingStyle value="Size" />

<maxSizeRollBackups value="10" />

<maximumFileSize value="100KB" />

<staticLogFileName value="true" />

<layout type="log4net.Layout.PatternLayout">

<conversionPattern value="%date [%thread] (%file:%line) %-5level %logger [%property{NDC}] - %message%newline" />

</layout>

</appender>

<appender name="RollingFileAppender" type="log4net.Appender.RollingFileAppender">
<file value="RollingFileAppender_log.txt" />
<appendToFile value="true" />
<rollingStyle value="Size" />
<maxSizeRollBackups value="10" />
<maximumFileSize value="100KB" />
<staticLogFileName value="true" />
<layout type="log4net.Layout.PatternLayout">
<conversionPattern value="%date [%thread] (%file:%line) %-5level %logger [%property{NDC}] - %message%newline" />
</layout>
</appender>

在上面的配置中，每个日志文件最大100KB，最大日志文件个数是10生成的日志文件名会是RollingFileAppender_log.txt.1, RollingFileAppender_log.txt.2 ... RollingFileAppender_log.txt.10，如果记录的日志超过10个，会从RollingFileAppender_log.txt.1开始覆盖。
还有一种方式就是按照日期记录日志，它的配置如下：

<appender name="RollingLogFileAppender_DateFormat" type="log4net.Appender.RollingFileAppender">

<file value="RollingLogFileAppender_DateFormat_log.txt" />

<appendToFile value="true" />

<rollingStyle value="Date" />

<!--<datePattern value="yyyyMMdd-HHmm" />-->

<datePattern value="yyyyMMdd" />

<layout type="log4net.Layout.PatternLayout">

<conversionPattern value="%date [%thread](%file:%line) %-5level %logger [%property{NDC}] - %message%newline" />

</layout>

</appender>

<root>

<!--文件形式记录日志-->

<appender-ref ref="LogFileAppender" />

<!--控制台控制显示日志-->

<appender-ref ref="ConsoleAppender" />

<!--Windows事件日志-->

<!--<appender-ref ref="EventLogAppender" />-->

<!--SQLite事件日志-->

<appender-ref ref="AdoNetAppender_SQLite" />

<!--RollingFileAppender事件日志-->

<appender-ref ref="RollingFileAppender" />

<!--RollingFileAppender事件日志，每天一个日志-->

<appender-ref ref="RollingLogFileAppender_DateFormat" />

<!-- 如果不启用相应的日志记录，可以通过这种方式注释掉

<appender-ref ref="AdoNetAppender_Access" />

-->

</root>

<root>
<!--文件形式记录日志-->
<appender-ref ref="LogFileAppender" />
<!--控制台控制显示日志-->
<appender-ref ref="ConsoleAppender" />
<!--Windows事件日志-->
<!--<appender-ref ref="EventLogAppender" />-->
<!--SQLite事件日志-->
<appender-ref ref="AdoNetAppender_SQLite" />
<!--RollingFileAppender事件日志-->
<appender-ref ref="RollingFileAppender" />
<!--RollingFileAppender事件日志，每天一个日志-->
<appender-ref ref="RollingLogFileAppender_DateFormat" />
<!-- 如果不启用相应的日志记录，可以通过这种方式注释掉
<appender-ref ref="AdoNetAppender_Access" />
-->
</root>

在上面的例子中可以看出，如果想增加日志输出目的地，增加<appender-ref>节点就是了，注意后面的ref是在config中配置的appender name，如果想要取消，删除或者注释掉这行就可以了。
Log4Net的使用
首先要添加config文件，在类库项目、命令行程序及WinForm中添加的是app.config，在WebForm中添加的是web.config。
下面是一个在WinForm项目中的使用Log4Net的例子：

using System.Collections.Generic;

using System.Text;

using log4net;

using System.Reflection;

//注意下面的语句一定要加上，指定log4net使用.config文件来读取配置信息

//如果是WinForm（假定程序为MyDemo.exe，则需要一个MyDemo.exe.config文件）

//如果是WebForm，则从web.config中读取相关信息

[assembly: log4net.Config.XmlConfigurator(Watch = true)]

namespace Log4NetDemo

{

class Program

{

static void Main(string[] args)

{

Random random = new Random();

for (int i = 0; i < 1; i++)

{

//创建日志记录组件实例

//ILog log = log4net.LogManager.GetLogger(MethodBase.GetCurrentMethod().DeclaringType);

ILog log=log4net.LogManager.GetLogger(typeof(Program));

//记录错误日志

//log.Error("error", new Exception("在这里发生了一个异常,Error Number:"+random.Next()));

//记录严重错误

//log.Fatal("fatal", new Exception("在发生了一个致命错误，Exception Id："+random.Next()));

//记录一般信息

//log.Info("提示：系统正在运行");

//记录调试信息

//log.Debug("调试信息：debug");

//记录警告信息

//log.Warn("警告：warn");

}

Console.WriteLine("日志记录完毕。");

Console.Read();

}

}

}

using System;

using System.Collections.Generic;

using System.Web;

using System.Web.UI;

using System.Web.UI.WebControls;

using log4net;

using System.Reflection;

//如果是web项目，需要在global.asax的Application_Start方法中配置web.config的引用,log4net.Config.XmlConfigurator.Configure();

[assembly: log4net.Config.XmlConfigurator(Watch = true)]

public partial class _Default : System.Web.UI.Page

{

protected void Page_Load(object sender, EventArgs e)

{

if (!Page.IsPostBack)

{

Random random = new Random();

for (int i = 0; i < 1; i++)

{

//创建日志记录组件实例

ILog log = log4net.LogManager.GetLogger(MethodBase.GetCurrentMethod().DeclaringType);

//ILog log = log4net.LogManager.GetLogger(typeof(Program));

//记录错误日志

//log.Error("error", new Exception("在这里发生了一个异常,Error Number:"+random.Next()));

//记录严重错误

//log.Fatal("fatal", new Exception("在发生了一个致命错误，Exception Id："+random.Next()));

//记录一般信息

//log.Info("提示：系统正在运行");

//记录调试信息

//log.Debug("调试信息：debug");

//记录警告信息

log.Warn("警告：warn");

Response.Write("日志记录完毕。");

}

}

}

}

using System;
using System.Collections.Generic;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using log4net;
using System.Reflection;

//如果是web项目，需要在global.asax的Application_Start方法中配置web.config的引用,log4net.Config.XmlConfigurator.Configure();
[assembly: log4net.Config.XmlConfigurator(Watch = true)]
public partial class _Default : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
if (!Page.IsPostBack)
{
Random random = new Random();
for (int i = 0; i < 1; i++)
{
//创建日志记录组件实例
ILog log = log4net.LogManager.GetLogger(MethodBase.GetCurrentMethod().DeclaringType);

//ILog log = log4net.LogManager.GetLogger(typeof(Program));
//记录错误日志
//log.Error("error", new Exception("在这里发生了一个异常,Error Number:"+random.Next()));
//记录严重错误
//log.Fatal("fatal", new Exception("在发生了一个致命错误，Exception Id："+random.Next()));
//记录一般信息
//log.Info("提示：系统正在运行");
//记录调试信息
//log.Debug("调试信息：debug");
//记录警告信息
log.Warn("警告：warn");
Response.Write("日志记录完毕。");
}
}
}
}

可以看出它们的代码基本没有区别。

下面是一个在WinForm下的config文件的完整配置，该配置文件所使用的代码就是在上面所使用到的代码，使用LogFileAppender、ConsoleAppender、EventLogAppender、AdoNetAppender_SQLite、RollingFileAppender、RollingLogFileAppender_DateFormat方式记录日志都在本地通过测试。完整的config文件代码如下：

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

<configuration>

<configSections>

<section name="log4net" type="System.Configuration.IgnoreSectionHandler"/>

</configSections>

<appSettings>

<!-- To enable internal log4net logging specify the

following appSettings key -->

<add key="log4net.Internal.Debug" value="true"/>

</appSettings>

<log4net>

<!--定义输出到文件中-->

<appender name="LogFileAppender" type="log4net.Appender.FileAppender">

<!--每条日志末尾的文字说明-->

<footer value="by 周公" />

<!--定义文件存放位置-->

<file value="LogFileAppender_log.txt" />

<appendToFile value="true" />

<datePattern value="yyyyMMdd-HH:mm:ss" />

<layout type="log4net.Layout.PatternLayout">

<!--每条日志末尾的文字说明-->

<footer value="by 周公" />

<!--输出格式-->

<!--样例：2010-11-17 15:50:23,443 [9] (D:/CSProjects/Log4NetDemo/Log4NetDemo/Program.cs:27) FATAL Log4NetDemo.Program [(null)] - fatal

System.Exception: 在发生了一个致命错误，Exception Id：548828745-->

<conversionPattern value="记录时间：%date 线程ID:[%thread] 日志级别：文件：所在行%-5level 出错类：%logger property:[%property{NDC}] - 错误描述：%message%newline" />

</layout>

</appender>

<!--定义输出到控制台命令行中-->

<appender name="ConsoleAppender" type="log4net.Appender.ConsoleAppender">

<layout type="log4net.Layout.PatternLayout">

<conversionPattern value="%date [%thread] (%file:%line) %-5level %logger [%property{NDC}] - %message%newline" />

</layout>

</appender>

<!--使用Rolling方式记录日志

每个日志文件最大100KB，生成的日志文件名会是log.txt.1,log.txt.2 ...log.txt.10

如果记录的日志超过10个，会从log.txt.1开始覆盖

-->

<appender name="RollingFileAppender" type="log4net.Appender.RollingFileAppender">

<file value="RollingFileAppender_log.txt" />

<appendToFile value="true" />

<rollingStyle value="Size" />

<maxSizeRollBackups value="10" />

<maximumFileSize value="100KB" />

<staticLogFileName value="true" />

<layout type="log4net.Layout.PatternLayout">

<conversionPattern value="%date [%thread] (%file:%line) %-5level %logger [%property{NDC}] - %message%newline" />

</layout>

</appender>

<!--使用Rolling方式记录日志

按照日来记录日志

-->

<appender name="RollingLogFileAppender_DateFormat" type="log4net.Appender.RollingFileAppender">

<file value="RollingLogFileAppender_DateFormat_log.txt" />

<appendToFile value="true" />

<rollingStyle value="Date" />

<!--<datePattern value="yyyyMMdd-HHmm" />-->

<datePattern value="yyyyMMdd" />

<layout type="log4net.Layout.PatternLayout">

<conversionPattern value="%date [%thread](%file:%line) %-5level %logger [%property{NDC}] - %message%newline" />

</layout>

</appender>

<!--记录到SQLite这样的单机数据库中去

创SQLite表的SQL语句：

CREATE TABLE Log (

LogId INTEGER PRIMARY KEY,

Date DATETIME NOT NULL,

Level VARCHAR(50) NOT NULL,

Logger VARCHAR(255) NOT NULL,

Source VARCHAR(255) NOT NULL,

Message TEXT DEFAULT NULL

);

-->

<appender name="AdoNetAppender_SQLite" type="log4net.Appender.AdoNetAppender">

<bufferSize value="100" />

<connectionType value="System.Data.SQLite.SQLiteConnection, System.Data.SQLite, Version=1.0.66.0, Culture=neutral" />

<!--SQLite连接字符串-->

<connectionString value="Data Source=c://log4net.db;Version=3;" />

<commandText value="INSERT INTO Log (Date, Level, Logger,Source, Message) VALUES (@Date, @Level, @Logger, @Source, @Message)" />

<parameter>

<parameterName value="@Date" />

<dbType value="DateTime" />

<layout type="log4net.Layout.RawTimeStampLayout" />

</parameter>

<parameter>

<parameterName value="@Level" />

<dbType value="String" />

<layout type="log4net.Layout.PatternLayout">

<conversionPattern value="%level" />

</layout>

</parameter>

<parameter>

<parameterName value="@Logger" />

<dbType value="String" />

<layout type="log4net.Layout.PatternLayout">

<conversionPattern value="%logger" />

</layout>

</parameter>

<parameter>

<parameterName value="@Source" />

<dbType value="String" />

<layout type="log4net.Layout.PatternLayout">

<conversionPattern value="%file:%line" />

</layout>

</parameter>

<parameter>

<parameterName value="@Message" />

<dbType value="String" />

<layout type="log4net.Layout.PatternLayout">

<conversionPattern value="%message" />

</layout>

</parameter>

</appender>

<!--定义输出到SQL Server数据库中-->

<!--

在SQL Server中创建表的SQL语句

CREATE TABLE [dbo].[Log] (

[Id] [int] IDENTITY (1, 1) NOT NULL,

[Date] [datetime] NOT NULL,

[Thread] [varchar] (255) NOT NULL,

[Level] [varchar] (50) NOT NULL,

[Logger] [varchar] (255) NOT NULL,

[Message] [varchar] (4000) NOT NULL,

[Exception] [varchar] (2000) NULL

);

-->

<appender name="AdoNetAppender_SQLServer" type="log4net.Appender.AdoNetAppender">

<bufferSize value="100" />

<connectionType value="System.Data.SqlClient.SqlConnection, System.Data" />

<connectionString value="data source=[database server];initial catalog=[database name];integrated security=false;persist security info=True;User ID=[user];Password=[password]" />

<commandText value="INSERT INTO Log ([Date],[Thread],[Level],[Logger],[Message],[Exception]) VALUES (@log_date, @thread, @log_level, @logger, @message, @exception)" />

<parameter>

<parameterName value="@log_date" />

<dbType value="DateTime" />

<layout type="log4net.Layout.RawTimeStampLayout" />

</parameter>

<parameter>

<parameterName value="@thread" />

<dbType value="String" />

<size value="255" />

<layout type="log4net.Layout.PatternLayout">

<conversionPattern value="%thread" />

</layout>

</parameter>

<parameter>

<parameterName value="@log_level" />

<dbType value="String" />

<size value="50" />

<layout type="log4net.Layout.PatternLayout">

<conversionPattern value="%level" />

</layout>

</parameter>

<parameter>

<parameterName value="@logger" />

<dbType value="String" />

<size value="255" />

<layout type="log4net.Layout.PatternLayout">

<conversionPattern value="%logger" />

</layout>

</parameter>

<parameter>

<parameterName value="@message" />

<dbType value="String" />

<size value="4000" />

<layout type="log4net.Layout.PatternLayout">

<conversionPattern value="%message" />

</layout>

</parameter>

<parameter>

<parameterName value="@exception" />

<dbType value="String" />

<size value="2000" />

<layout type="log4net.Layout.ExceptionLayout" />

</parameter>

</appender>

<!--定义输出到Oracle9i中-->

<!--

在Oracle9i中创建表的SQL语句

create table log (

Datetime timestamp(3),

Thread varchar2(255),

Log_Level varchar2(255),

Logger varchar2(255),

Message varchar2(4000)

);

-->

<appender name="AdoNetAppender_Oracle" type="log4net.Appender.AdoNetAppender">

<connectionType value="System.Data.OracleClient.OracleConnection, System.Data.OracleClient" />

<connectionString value="data source=[mydatabase];User ID=[user];Password=[password]" />

<commandText value="INSERT INTO Log (Datetime,Thread,Log_Level,Logger,Message) VALUES (:log_date, :thread, :log_level, :logger, :message)" />

<bufferSize value="128" />

<parameter>

<parameterName value=":log_date" />

<dbType value="DateTime" />

<layout type="log4net.Layout.RawTimeStampLayout" />

</parameter>

<parameter>

<parameterName value=":thread" />

<dbType value="String" />

<size value="255" />

<layout type="log4net.Layout.PatternLayout">

<conversionPattern value="%thread" />

</layout>

</parameter>

<parameter>

<parameterName value=":log_level" />

<dbType value="String" />

<size value="50" />

<layout type="log4net.Layout.PatternLayout">

<conversionPattern value="%level" />

</layout>

</parameter>

<parameter>

<parameterName value=":logger" />

<dbType value="String" />

<size value="255" />

<layout type="log4net.Layout.PatternLayout">

<conversionPattern value="%logger" />

</layout>

</parameter>

<parameter>

<parameterName value=":message" />

<dbType value="String" />

<size value="4000" />

<layout type="log4net.Layout.PatternLayout">

<conversionPattern value="%message" />

</layout>

</parameter>

</appender>

<!--定义输出到IBM DB2中-->

<!--

在DB2中创建表的SQL语句

CREATE TABLE "myschema.LOG" (

"ID" INTEGER NOT NULL GENERATED ALWAYS AS IDENTITY (

START WITH +1

INCREMENT BY +1

MINVALUE +1

MAXVALUE +2147483647

NO CYCLE

NO CACHE

NO ORDER

),

"DATE" TIMESTAMP NOT NULL,

"THREAD" VARCHAR(255) NOT NULL,

"LEVEL" VARCHAR(500) NOT NULL,

"LOGGER" VARCHAR(255) NOT NULL,

"MESSAGE" VARCHAR(4000) NOT NULL,

"EXCEPTION" VARCHAR(2000)

)

IN "LRGTABLES";

-->

<appender name="AdoNetAppender_DB2" type="log4net.Appender.AdoNetAppender">

<bufferSize value="100" />

<connectionType value="IBM.Data.DB2.DB2Connection,IBM.Data.DB2" />

<connectionString value="server=192.168.0.0;database=dbuser;user Id=username;password=password;persist security info=true" />

<commandText value="INSERT INTO myschema.Log (Date,Thread,Level,Logger,Message,Exception) VALUES (@log_date,@thread,@log_level,@logger,@message,@exception)" />

<parameter>

<parameterName value="@log_date" />

<dbType value="DateTime" />

<layout type="log4net.Layout.RawTimeStampLayout" />

</parameter>

<parameter>

<parameterName value="@thread" />

<dbType value="String" />

<size value="255" />

<layout type="log4net.Layout.PatternLayout">

<conversionPattern value="%thread" />

</layout>

</parameter>

<parameter>

<parameterName value="@log_level" />

<dbType value="String" />

<size value="500" />

<layout type="log4net.Layout.PatternLayout">

<conversionPattern value="%level" />

</layout>

</parameter>

<parameter>

<parameterName value="@logger" />

<dbType value="String" />

<size value="255" />

<layout type="log4net.Layout.PatternLayout">

<conversionPattern value="%logger" />

</layout>

</parameter>

<parameter>

<parameterName value="@message" />

<dbType value="String" />

<size value="4000" />

<layout type="log4net.Layout.PatternLayout">

<conversionPattern value="%message" />

</layout>

</parameter>

<parameter>

<parameterName value="@exception" />

<dbType value="String" />

<size value="2000" />

<layout type="log4net.Layout.ExceptionLayout" />

</parameter>

</appender>

<!--定义输出到windows事件中-->

<appender name="EventLogAppender" type="log4net.Appender.EventLogAppender">

<layout type="log4net.Layout.PatternLayout">

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

</layout>

</appender>

<!--定义输出到数据库中，这里举例输出到Access数据库中，数据库为C盘的log4net.mdb

创建Access表的SQL语句：

-->

<appender name="AdoNetAppender_Access" type="log4net.Appender.AdoNetAppender">

<connectionString value="Provider=Microsoft.Jet.OLEDB.4.0;Data Source=C:/log4net.mdb" />

<commandText value="INSERT INTO LogDetails ([LogDate],[Thread],[Level],[Logger],[Message]) VALUES (@logDate, @thread, @logLevel, @logger,@message)" />

<!--定义各个参数-->

<parameter>

<parameterName value="@logDate" />

<dbType value="String" />

<size value="240" />

<layout type="log4net.Layout.PatternLayout">

<conversionPattern value="%date" />

</layout>

</parameter>

<parameter>

<parameterName value="@thread" />

<dbType value="String" />

<size value="240" />

<layout type="log4net.Layout.PatternLayout">

<conversionPattern value="%thread" />

</layout>

</parameter>

<parameter>

<parameterName value="@logLevel" />

<dbType value="String" />

<size value="240" />

<layout type="log4net.Layout.PatternLayout">

<conversionPattern value="%level" />

</layout>

</parameter>

<parameter>

<parameterName value="@logger" />

<dbType value="String" />

<size value="240" />

<layout type="log4net.Layout.PatternLayout">

<conversionPattern value="%logger" />

</layout>

</parameter>

<parameter>

<parameterName value="@message" />

<dbType value="String" />

<size value="240" />

<layout type="log4net.Layout.PatternLayout">

<conversionPattern value="%message" />

</layout>

</parameter>

</appender>

<!--定义日志的输出媒介，下面定义日志以四种方式输出。也可以下面的按照一种类型或其他类型输出。-->

<root>

<!--文件形式记录日志-->

<appender-ref ref="LogFileAppender" />

<!--控制台控制显示日志-->

<appender-ref ref="ConsoleAppender" />

<!--Windows事件日志-->

<!--<appender-ref ref="EventLogAppender" />-->

<!--SQLite日志-->

<!--<appender-ref ref="AdoNetAppender_SQLite" />-->

<!--RollingFileAppender事件日志-->

<appender-ref ref="RollingFileAppender" />

<!--RollingFileAppender事件日志，每天一个日志-->

<appender-ref ref="RollingLogFileAppender_DateFormat" />

<!-- 如果不启用相应的日志记录，可以通过这种方式注释掉

<appender-ref ref="AdoNetAppender_Access" />

-->

</root>

</log4net>

<!--<system.diagnostics>

<trace autoflush="true">

<listeners>

<add

name="textWriterTraceListener"

type="System.Diagnostics.TextWriterTraceListener"

initializeData="D:/CSProjects/Log4NetDemo/Log4NetDemo/bin/log4net.txt" />

</listeners>

</trace>

</system.diagnostics>-->

</configuration>

<?xml version="1.0" encoding="utf-8" ?>
<configuration>
<configSections>
<section name="log4net" type="System.Configuration.IgnoreSectionHandler"/>
</configSections>
<appSettings>
<!-- To enable internal log4net logging specify the
following appSettings key -->
<add key="log4net.Internal.Debug" value="true"/>
</appSettings>
<log4net>
<!--定义输出到文件中-->
<appender name="LogFileAppender" type="log4net.Appender.FileAppender">
<!--每条日志末尾的文字说明-->
<footer value="by 周公" />
<!--定义文件存放位置-->
<file value="LogFileAppender_log.txt" />
<appendToFile value="true" />
<datePattern value="yyyyMMdd-HH:mm:ss" />
<layout type="log4net.Layout.PatternLayout">
<!--每条日志末尾的文字说明-->
<footer value="by 周公" />
<!--输出格式-->
<!--样例：2010-11-17 15:50:23,443 [9] (D:/CSProjects/Log4NetDemo/Log4NetDemo/Program.cs:27) FATAL Log4NetDemo.Program [(null)] - fatal
System.Exception: 在发生了一个致命错误，Exception Id：548828745-->
<conversionPattern value="记录时间：%date 线程ID:[%thread] 日志级别：文件：所在行%-5level 出错类：%logger property:[%property{NDC}] - 错误描述：%message%newline" />
</layout>
</appender>
<!--定义输出到控制台命令行中-->
<appender name="ConsoleAppender" type="log4net.Appender.ConsoleAppender">
<layout type="log4net.Layout.PatternLayout">
<conversionPattern value="%date [%thread] (%file:%line) %-5level %logger [%property{NDC}] - %message%newline" />
</layout>
</appender>
<!--使用Rolling方式记录日志
每个日志文件最大100KB，生成的日志文件名会是log.txt.1,log.txt.2 ...log.txt.10
如果记录的日志超过10个，会从log.txt.1开始覆盖
-->
<appender name="RollingFileAppender" type="log4net.Appender.RollingFileAppender">
<file value="RollingFileAppender_log.txt" />
<appendToFile value="true" />
<rollingStyle value="Size" />
<maxSizeRollBackups value="10" />
<maximumFileSize value="100KB" />
<staticLogFileName value="true" />
<layout type="log4net.Layout.PatternLayout">
<conversionPattern value="%date [%thread] (%file:%line) %-5level %logger [%property{NDC}] - %message%newline" />
</layout>
</appender>
<!--使用Rolling方式记录日志
按照日来记录日志
-->
<appender name="RollingLogFileAppender_DateFormat" type="log4net.Appender.RollingFileAppender">
<file value="RollingLogFileAppender_DateFormat_log.txt" />
<appendToFile value="true" />
<rollingStyle value="Date" />
<!--<datePattern value="yyyyMMdd-HHmm" />-->
<datePattern value="yyyyMMdd" />
<layout type="log4net.Layout.PatternLayout">
<conversionPattern value="%date [%thread](%file:%line) %-5level %logger [%property{NDC}] - %message%newline" />
</layout>
</appender>

<!--记录到SQLite这样的单机数据库中去
创SQLite表的SQL语句：
CREATE TABLE Log (
LogId INTEGER PRIMARY KEY,
Date DATETIME NOT NULL,
Level VARCHAR(50) NOT NULL,
Logger VARCHAR(255) NOT NULL,
Source VARCHAR(255) NOT NULL,
Message TEXT DEFAULT NULL
);
-->
<appender name="AdoNetAppender_SQLite" type="log4net.Appender.AdoNetAppender">
<bufferSize value="100" />
<connectionType value="System.Data.SQLite.SQLiteConnection, System.Data.SQLite, Version=1.0.66.0, Culture=neutral" />
<!--SQLite连接字符串-->
<connectionString value="Data Source=c://log4net.db;Version=3;" />
<commandText value="INSERT INTO Log (Date, Level, Logger,Source, Message) VALUES (@Date, @Level, @Logger, @Source, @Message)" />
<parameter>
<parameterName value="@Date" />
<dbType value="DateTime" />
<layout type="log4net.Layout.RawTimeStampLayout" />
</parameter>
<parameter>
<parameterName value="@Level" />
<dbType value="String" />
<layout type="log4net.Layout.PatternLayout">
<conversionPattern value="%level" />
</layout>
</parameter>
<parameter>
<parameterName value="@Logger" />
<dbType value="String" />
<layout type="log4net.Layout.PatternLayout">
<conversionPattern value="%logger" />
</layout>
</parameter>
<parameter>
<parameterName value="@Source" />
<dbType value="String" />
<layout type="log4net.Layout.PatternLayout">
<conversionPattern value="%file:%line" />
</layout>
</parameter>
<parameter>
<parameterName value="@Message" />
<dbType value="String" />
<layout type="log4net.Layout.PatternLayout">
<conversionPattern value="%message" />
</layout>
</parameter>
</appender>
<!--定义输出到SQL Server数据库中-->
<!--
在SQL Server中创建表的SQL语句
CREATE TABLE [dbo].[Log] (
[Id] [int] IDENTITY (1, 1) NOT NULL,
[Date] [datetime] NOT NULL,
[Thread] [varchar] (255) NOT NULL,
[Level] [varchar] (50) NOT NULL,
[Logger] [varchar] (255) NOT NULL,
[Message] [varchar] (4000) NOT NULL,
[Exception] [varchar] (2000) NULL
);
-->
<appender name="AdoNetAppender_SQLServer" type="log4net.Appender.AdoNetAppender">
<bufferSize value="100" />
<connectionType value="System.Data.SqlClient.SqlConnection, System.Data" />
<connectionString value="data source=[database server];initial catalog=[database name];integrated security=false;persist security info=True;User ID=[user];Password=[password]" />
<commandText value="INSERT INTO Log ([Date],[Thread],[Level],[Logger],[Message],[Exception]) VALUES (@log_date, @thread, @log_level, @logger, @message, @exception)" />
<parameter>
<parameterName value="@log_date" />
<dbType value="DateTime" />
<layout type="log4net.Layout.RawTimeStampLayout" />
</parameter>
<parameter>
<parameterName value="@thread" />
<dbType value="String" />
<size value="255" />
<layout type="log4net.Layout.PatternLayout">
<conversionPattern value="%thread" />
</layout>
</parameter>
<parameter>
<parameterName value="@log_level" />
<dbType value="String" />
<size value="50" />
<layout type="log4net.Layout.PatternLayout">
<conversionPattern value="%level" />
</layout>
</parameter>
<parameter>
<parameterName value="@logger" />
<dbType value="String" />
<size value="255" />
<layout type="log4net.Layout.PatternLayout">
<conversionPattern value="%logger" />
</layout>
</parameter>
<parameter>
<parameterName value="@message" />
<dbType value="String" />
<size value="4000" />
<layout type="log4net.Layout.PatternLayout">
<conversionPattern value="%message" />
</layout>
</parameter>
<parameter>
<parameterName value="@exception" />
<dbType value="String" />
<size value="2000" />
<layout type="log4net.Layout.ExceptionLayout" />
</parameter>
</appender>
<!--定义输出到Oracle9i中-->
<!--
在Oracle9i中创建表的SQL语句
create table log (
Datetime timestamp(3),
Thread varchar2(255),
Log_Level varchar2(255),
Logger varchar2(255),
Message varchar2(4000)
);
-->
<appender name="AdoNetAppender_Oracle" type="log4net.Appender.AdoNetAppender">
<connectionType value="System.Data.OracleClient.OracleConnection, System.Data.OracleClient" />
<connectionString value="data source=[mydatabase];User ID=[user];Password=[password]" />
<commandText value="INSERT INTO Log (Datetime,Thread,Log_Level,Logger,Message) VALUES (:log_date, :thread, :log_level, :logger, :message)" />
<bufferSize value="128" />
<parameter>
<parameterName value=":log_date" />
<dbType value="DateTime" />
<layout type="log4net.Layout.RawTimeStampLayout" />
</parameter>
<parameter>
<parameterName value=":thread" />
<dbType value="String" />
<size value="255" />
<layout type="log4net.Layout.PatternLayout">
<conversionPattern value="%thread" />
</layout>
</parameter>
<parameter>
<parameterName value=":log_level" />
<dbType value="String" />
<size value="50" />
<layout type="log4net.Layout.PatternLayout">
<conversionPattern value="%level" />
</layout>
</parameter>
<parameter>
<parameterName value=":logger" />
<dbType value="String" />
<size value="255" />
<layout type="log4net.Layout.PatternLayout">
<conversionPattern value="%logger" />
</layout>
</parameter>
<parameter>
<parameterName value=":message" />
<dbType value="String" />
<size value="4000" />
<layout type="log4net.Layout.PatternLayout">
<conversionPattern value="%message" />
</layout>
</parameter>
</appender>
<!--定义输出到IBM DB2中-->
<!--
在DB2中创建表的SQL语句
CREATE TABLE "myschema.LOG" (
"ID" INTEGER NOT NULL GENERATED ALWAYS AS IDENTITY (
START WITH +1
INCREMENT BY +1
MINVALUE +1
MAXVALUE +2147483647
NO CYCLE
NO CACHE
NO ORDER
),
"DATE" TIMESTAMP NOT NULL,
"THREAD" VARCHAR(255) NOT NULL,
"LEVEL" VARCHAR(500) NOT NULL,
"LOGGER" VARCHAR(255) NOT NULL,
"MESSAGE" VARCHAR(4000) NOT NULL,
"EXCEPTION" VARCHAR(2000)
)
IN "LRGTABLES";
-->
<appender name="AdoNetAppender_DB2" type="log4net.Appender.AdoNetAppender">
<bufferSize value="100" />
<connectionType value="IBM.Data.DB2.DB2Connection,IBM.Data.DB2" />
<connectionString value="server=192.168.0.0;database=dbuser;user Id=username;password=password;persist security info=true" />
<commandText value="INSERT INTO myschema.Log (Date,Thread,Level,Logger,Message,Exception) VALUES (@log_date,@thread,@log_level,@logger,@message,@exception)" />
<parameter>
<parameterName value="@log_date" />
<dbType value="DateTime" />
<layout type="log4net.Layout.RawTimeStampLayout" />
</parameter>
<parameter>
<parameterName value="@thread" />
<dbType value="String" />
<size value="255" />
<layout type="log4net.Layout.PatternLayout">
<conversionPattern value="%thread" />
</layout>
</parameter>
<parameter>
<parameterName value="@log_level" />
<dbType value="String" />
<size value="500" />
<layout type="log4net.Layout.PatternLayout">
<conversionPattern value="%level" />
</layout>
</parameter>
<parameter>
<parameterName value="@logger" />
<dbType value="String" />
<size value="255" />
<layout type="log4net.Layout.PatternLayout">
<conversionPattern value="%logger" />
</layout>
</parameter>
<parameter>
<parameterName value="@message" />
<dbType value="String" />
<size value="4000" />
<layout type="log4net.Layout.PatternLayout">
<conversionPattern value="%message" />
</layout>
</parameter>
<parameter>
<parameterName value="@exception" />
<dbType value="String" />
<size value="2000" />
<layout type="log4net.Layout.ExceptionLayout" />
</parameter>
</appender>
<!--定义输出到windows事件中-->
<appender name="EventLogAppender" type="log4net.Appender.EventLogAppender">
<layout type="log4net.Layout.PatternLayout">
<conversionPattern value="%date [%thread] %-5level %logger [%property{NDC}] - %message%newline" />
</layout>
</appender>
<!--定义输出到数据库中，这里举例输出到Access数据库中，数据库为C盘的log4net.mdb
创建Access表的SQL语句：
-->
<appender name="AdoNetAppender_Access" type="log4net.Appender.AdoNetAppender">
<connectionString value="Provider=Microsoft.Jet.OLEDB.4.0;Data Source=C:/log4net.mdb" />
<commandText value="INSERT INTO LogDetails ([LogDate],[Thread],[Level],[Logger],[Message]) VALUES (@logDate, @thread, @logLevel, @logger,@message)" />
<!--定义各个参数-->
<parameter>
<parameterName value="@logDate" />
<dbType value="String" />
<size value="240" />
<layout type="log4net.Layout.PatternLayout">
<conversionPattern value="%date" />
</layout>
</parameter>
<parameter>
<parameterName value="@thread" />
<dbType value="String" />
<size value="240" />
<layout type="log4net.Layout.PatternLayout">
<conversionPattern value="%thread" />
</layout>
</parameter>
<parameter>
<parameterName value="@logLevel" />
<dbType value="String" />
<size value="240" />
<layout type="log4net.Layout.PatternLayout">
<conversionPattern value="%level" />
</layout>
</parameter>
<parameter>
<parameterName value="@logger" />
<dbType value="String" />
<size value="240" />
<layout type="log4net.Layout.PatternLayout">
<conversionPattern value="%logger" />
</layout>
</parameter>
<parameter>
<parameterName value="@message" />
<dbType value="String" />
<size value="240" />
<layout type="log4net.Layout.PatternLayout">
<conversionPattern value="%message" />
</layout>
</parameter>
</appender>
<!--定义日志的输出媒介，下面定义日志以四种方式输出。也可以下面的按照一种类型或其他类型输出。-->
<root>
<!--文件形式记录日志-->
<appender-ref ref="LogFileAppender" />
<!--控制台控制显示日志-->
<appender-ref ref="ConsoleAppender" />
<!--Windows事件日志-->
<!--<appender-ref ref="EventLogAppender" />-->
<!--SQLite日志-->
<!--<appender-ref ref="AdoNetAppender_SQLite" />-->
<!--RollingFileAppender事件日志-->
<appender-ref ref="RollingFileAppender" />
<!--RollingFileAppender事件日志，每天一个日志-->
<appender-ref ref="RollingLogFileAppender_DateFormat" />
<!-- 如果不启用相应的日志记录，可以通过这种方式注释掉
<appender-ref ref="AdoNetAppender_Access" />
-->
</root>

</log4net>
<!--<system.diagnostics>
<trace autoflush="true">
<listeners>
<add
name="textWriterTraceListener"
type="System.Diagnostics.TextWriterTraceListener"
initializeData="D:/CSProjects/Log4NetDemo/Log4NetDemo/bin/log4net.txt" />
</listeners>
</trace>
</system.diagnostics>-->

</configuration>

总结：

本篇主要是补充在上一篇关于Log4Net中未尽之处，并集中详尽回答了一些朋友在该篇博文下的提问，如有未尽之处，请在本篇下留言。如有初学者碰巧路过不知config文件为何物，请看《asp.net夜话之十一：web.config详解》，网址是：http://blog.csdn.net/zhoufoxcn/archive/2008/11/10/3265141.aspx。