mvc中日志的原理和使用步骤

日志原理 就是观察者模式(订阅发布模式) , 具体和委托很像 

使用步骤  在 log4net框架下

1.在Common中定义LogHelper入口类

1.定义LogHelper类


namespace LTeasyOA.Common
{
public class LogHelper
{
public static Queue<string> ExceptionStringQueue = new Queue<string>();//日志消息队列
public static List<ILogWriter> LogWriterList = new List<ILogWriter>();//接受订阅者的集合   提供入口
public static void WriteLog(string exceptionText)   
{
lock (ExceptionStringQueue)
{
ExceptionStringQueue.Enqueue(exceptionText);
}
}

//静态函数的调用时机，是在类被实例化或者静态成员被调用的时候进行调用，
//并且是由.net框架来调用静态构造函数来初始化静态成员变量。

static LogHelper() //静态构造函数  只要是调用该类的任何构造方法 或实例化 都会调用此构造方法来初始化和执行日志函数
{

//LogWriterList.Add(new TextFileWrite());
//LogWriterList.Add(new SqlServerWriter());
LogWriterList.Add(new Log4NetWriter());  //添加订阅者  和委托赋值原理一样
ThreadPool.QueueUserWorkItem(o => {
lock (ExceptionStringQueue)
{
string str = ExceptionStringQueue.Dequeue();

//将异常信息写到日志文件中去 但有可能是文本文件 也可能是数据库文件
foreach (var ListItem in LogWriterList)
{
ListItem.WriteLogInfo(str);
}

//控件在这里帮我们自动实现 有一个框架 Log4Net

}
});
}
}
}

当然可以用多态

实现接口

namespace LTeasyOA.Common
{
public interface ILogWriter
{
void WriteLogInfo(string str);
}
}

子类实现

    public class Log4NetWriter:ILogWriter
    {
        public void WriteLogInfo(string str)
        {
            ILog logWriter = log4net.LogManager.GetLogger("Demo");
            logWriter.Error(str);
        }
    }

static LogHelper中实例化

2.

定义一个继承HandleErrorAttribute的子类 实现OnException()方法

namespace LTeasyOA.UI.Portal2.Models
{
    public class MyExceptionFilterAttribute:HandleErrorAttribute
    {
        public override void OnException(ExceptionContext filterContext)
        {
            //直接把错误写到 日志中去
            base.OnException(filterContext);
            Common.LogHelper.WriteLog(filterContext.Exception.ToString());
        }
    }
}

filterConfig中添加过滤器

using LTeasyOA.UI.Portal2.Models;
using System.Web;
using System.Web.Mvc;

namespace LTeasyOA.UI.Portal2
{
    public class FilterConfig
    {
        public static void RegisterGlobalFilters(GlobalFilterCollection filters)
        {
            //filters.Add(new HandleErrorAttribute());
            filters.Add(new MyExceptionFilterAttribute());
            //第一步
            // 过滤器 目前三种  ActionFilter ResultFilter ExceptionFilter
        }
    }
}

 web.config添加配置 两步

1.块配置

<section name="entityFramework" type="System.Data.Entity.Internal.ConfigFile.EntityFrameworkSection, EntityFramework, Version=5.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" requirePermission="false" />
<section name="log4net" type="log4net.Config.Log4NetConfigurationSectionHandler, log4net"/>
</configSections>

2.log4net节点配置

<log4net>
    <!-- OFF, FATAL, ERROR, WARN, INFO, DEBUG, ALL -->
    <!-- Set root logger level to ERROR and its appenders -->
    <root>
      <level value="ERROR"/>
      <appender-ref ref="SysAppender"/>
    </root>

    <!-- Print only messages of level DEBUG or above in the packages -->
    <logger name="WebLogger">
      <level value="DEBUG"/>
    </logger>

    <appender name="SysAppender" type="log4net.Appender.RollingFileAppender,log4net" >
      <param name="File" value="App_Data/" />
      <param name="AppendToFile" value="true" />
      <param name="RollingStyle" value="Date" />
      <param name="DatePattern" value="&quot;Logs_&quot;yyyyMMdd&quot;.txt&quot;" />
      <param name="StaticLogFileName" value="false" />
      <layout type="log4net.Layout.PatternLayout,log4net">
        <param name="ConversionPattern" value="%d [%t] %-5p %c - %m%n" />
        <param name="日志开始" value="&#13;&#10;----------------------header--------------------------&#13;&#10;" />
        <param name="日志结束" value="&#13;&#10;----------------------footer--------------------------&#13;&#10;" />
      </layout>
    </appender>
    <appender name="consoleApp" type="log4net.Appender.ConsoleAppender,log4net">
      <layout type="log4net.Layout.PatternLayout,log4net">
        <param name="ConversionPattern" value="%d [%t] %-5p %c - %m%n" />
      </layout>
    </appender>
  </log4net>

global中初始化

    public class MvcApplication : Spring.Web.Mvc.SpringMvcApplication
    {
        protected void Application_Start()
        {
            AreaRegistration.RegisterAllAreas();
            WebApiConfig.Register(GlobalConfiguration.Configuration);
            FilterConfig.RegisterGlobalFilters(GlobalFilters.Filters);
            RouteConfig.RegisterRoutes(RouteTable.Routes);
            BundleConfig.RegisterBundles(BundleTable.Bundles);

            //加载配置 初始化
            log4net.Config.XmlConfigurator.Configure();
        }
    }

测试

大功告成!!!!!