有時候Asp.net 、web service或寫 C# 會需要紀錄程式的log，
自己寫個文字檔當記錄也是可以，但是如果有現成的就不用自己刻。
這裡整理一下log4net的幾種用法，做為參考
本篇介紹Asp.net WebApplication 有IIS的case
如果你有先玩過log4net再來看這篇!!!
網路上教學很多都是需要在Global.asax 上啟用
這會遇到一個問題，如果IIS(機器)在人家手上，可不能給我上線每次說啟用就啟用
有時候軟重啟(ReStart)IIS 都要求人家幫你開，太痛苦了...
正在run 又要同時上新功能的也不可能讓你把IIS停下來
如果你所有的common log都是寫在同一個log file
你也不太可能在新上版的程式裡隨意的加上
Shutdown
log.Logger.Repository.Shutdown();
然後每次呼叫方法時，都開開關關這樣，
這樣搞，共用log有可能被你關掉導致其他程式無法寫入
下面提供一個範例，Dyamic Logger動態的產生一個實體Logger
範例中的寫法不需要吃外部Xml config，
要吃也可以啦，看你要吃什麼設定檔什麼參數，
拉出去吃Web.config或自訂XML都可以。
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using log4net;
using System.Reflection;
//using log4net.Config;
//using log4net.Repository.Hierarchy;
//using log4net.Appender;
//using log4net.Layout;
//using log4net.Core;
namespace WebApp_log4net
{
public class HandlerforLog : IHttpHandler
{
public void ProcessRequest(HttpContext context)
{
Write("Application is starting");
context.Response.ContentType = "text/plain";
context.Response.Write("Hello World");
}
public void Write(String message)
{
ILog myLog = GetDyamicLogger();
myLog.Info("[Write]:" + message);
}
public static ILog GetDyamicLogger()
{
log4net.Repository.Hierarchy.Hierarchy hierarchy =
(log4net.Repository.Hierarchy.Hierarchy)LogManager.GetRepository();
log4net.Appender.RollingFileAppender roller =
new log4net.Appender.RollingFileAppender();
roller.LockingModel = new log4net.Appender.FileAppender.MinimalLock();
roller.AppendToFile = true;
roller.RollingStyle =
log4net.Appender.RollingFileAppender.RollingMode.Composite;
roller.MaxSizeRollBackups = 29; // 0~29 is 30.
roller.MaximumFileSize = "10MB";
roller.DatePattern = "yyyyMMdd";
roller.Layout = new log4net.Layout.PatternLayout();
roller.File = "log\\debug.log";
roller.StaticLogFileName = true;
log4net.Layout.PatternLayout patternLayout =
new log4net.Layout.PatternLayout();
patternLayout.ConversionPattern =
@"%date [%thread] %-5level %logger [%property{NDC}] - %message%newline";
patternLayout.ActivateOptions();
roller.Layout = patternLayout;
roller.ActivateOptions();
hierarchy.Root.AddAppender(roller);
hierarchy.Root.Level = log4net.Core.Level.All;
hierarchy.Configured = true;
DummyLogger dummyILogger = new DummyLogger("LogName");
dummyILogger.Hierarchy = hierarchy;
dummyILogger.Level = log4net.Core.Level.All;
dummyILogger.AddAppender(roller);
return new log4net.Core.LogImpl(dummyILogger);
}
internal sealed class DummyLogger : log4net.Repository.Hierarchy.Logger
{
// Methods
internal DummyLogger(string name)
: base(name)
{
}
}
public bool IsReusable
{
get
{
return false;
}
}
}
}
參考資料
http://amolgangawane.blogspot.tw/
http://www.howtosolvenow.com/2014/01/log4net-example-in-c-console-application/
http://www.curlette.com/?p=1113
http://interactivelogic.net/wp/2010/02/aspnet-logging-to-output-window-with-log4net/
http://weblogs.asp.net/stevewellens/log4net-log-to-a-javascript-console
http://www.howtosolvenow.com/2014/01/log4net-example-in-c-console-application/
