C# 简易异步日志类 [ C# | Log | TextWriterTraceListener ]

// =========================================
//
//  作 者：农民伯伯
//  邮 箱：over140@gmail.com
//  博 客： http://over140.cnblogs.com/
//  时 间：2009-7-16
//  描 述：日志类，注意需要在日志记录的目录给用户写入权限!
//
// =========================================

using  System;
using  System.Configuration;
using  System.Collections.Generic;
using  System.Data.SqlClient;
using  System.Diagnostics;
using  System.IO;
using  System.Text;
using  System.Runtime.CompilerServices;
using  System.Web;


namespace  CentralHousesTest
{
     ///   <summary>
     ///  日志类
     ///   </summary>
     public   sealed   class  Logger
    {
         #region  Member Variables

         ///   <summary>
         ///  用于Trace的组织输出的类别名称
         ///   </summary>
         private   const   string  trace_sql  =   " \r\n***********************TRACE_SQL {0}*****************************\r\nTRACE_SQL " ;

         ///   <summary>
         ///  用于Trace的组织输出的类别名称
         ///   </summary>
         private   const   string  trace_exception  =   " \r\n***********************TRACE_EXCEPTION {0}*********************** " ;

         ///   <summary>
         ///  当前日志的日期
         ///   </summary>
         private   static  DateTime CurrentLogFileDate  =  DateTime.Now;

         ///   <summary>
         ///  日志对象
         ///   </summary>
         private   static  TextWriterTraceListener twtl;

         ///   <summary>
         ///  日志根目录
         ///   </summary>
         private   const   string  log_root_directory  =   @" D:\log " ;

         ///   <summary>
         ///  日志子目录
         ///   </summary>
         private   static   string  log_subdir;


         ///   <summary>
         ///  "      {0} = {1}"
         ///   </summary>
         private   const   string  FORMAT_TRACE_PARAM  =   "       {0} = {1} " ;

         ///   <summary>
         ///  1   仅控制台输出
         ///  2   仅日志输出
         ///  3   控制台+日志输出
         ///   </summary>
         private   static   readonly   int  flag  =   2 ;          // 可以修改成从配置文件读取

         #endregion

         #region  Constructor

         static  Logger()
        {
            System.Diagnostics.Trace.AutoFlush  =   true ;

             switch  (flag)
            {
                 case   1 :
                    System.Diagnostics.Trace.Listeners.Add( new  ConsoleTraceListener());
                     break ;
                 case   2 :
                    System.Diagnostics.Trace.Listeners.Add(TWTL);
                     break ;
                 case   3 :
                    System.Diagnostics.Trace.Listeners.Add( new  ConsoleTraceListener());
                    System.Diagnostics.Trace.Listeners.Add(TWTL);
                     break ;
            }
        }

         #endregion

         #region  Method

         #region  trace

         ///   <summary>
         ///  异步错误日志
         ///   </summary>
         ///   <param name="value"></param>
         public   static   void  Trace(Exception ex)
        {
             new  AsyncLogException(BeginTraceError).BeginInvoke(ex,  null ,  null );
        }

         ///   <summary>
         ///  异步SQL日志
         ///   </summary>
         ///   <param name="cmd"></param>
         public   static   void  Trace(SqlCommand cmd)
        {
             new  AsyncLogSqlCommand(BeginTraceSqlCommand).BeginInvoke(cmd,  null ,  null );
        }

         ///   <summary>
         ///  异步SQL日志
         ///   </summary>
         ///   <param name="sql"></param>
         ///   <param name="parameter"></param>
         public   static   void  Trace( string  sql,  params  SqlParameter[] parameter)
        {
             new  AsyncLogSql(BeginTraceSql).BeginInvoke(sql, parameter,  null ,  null );
        }

         #endregion

         #region  delegate

         private   delegate   void  AsyncLogException(Exception ex);
         private   delegate   void  AsyncLogSqlCommand(SqlCommand cmd);
         private   delegate   void  AsyncLogSql( string  sql,  params  SqlParameter[] parameter);

         private   static   void  BeginTraceError(Exception ex)
        {
             if  ( null   !=  ex)
            {
                 // 检测日志日期
                StrategyLog();

                 // 输出日志头
                System.Diagnostics.Trace.WriteLine( string .Format(trace_exception, DateTime.Now));
                 while  ( null   !=  ex)
                {
                    System.Diagnostics.Trace.WriteLine( string .Format( " {0} {1}\r\n{2}\r\nSource:{3} " , ex.GetType().Name, ex.Message, ex.StackTrace, ex.Source));
                    ex  =  ex.InnerException;
                }
            }
        }

         private   static   void  BeginTraceSqlCommand(SqlCommand cmd)
        {
             if  ( null   !=  cmd)
            {
                SqlParameter[] parameter  =   new  SqlParameter[cmd.Parameters.Count];
                cmd.Parameters.CopyTo(parameter,  0 );
                BeginTraceSql(cmd.CommandText, parameter);
            }
        }

         private   static   void  BeginTraceSql( string  sql,  params  SqlParameter[] parameter)
        {
             if  ( ! string .IsNullOrEmpty(sql))
            {
                 // 检测日志日期
                StrategyLog();

                System.Diagnostics.Trace.WriteLine(sql,  string .Format(trace_sql, DateTime.Now));
                 if  (parameter  !=   null )
                {
                     foreach  (SqlParameter param  in  parameter)
                    {
                        System.Diagnostics.Trace.WriteLine( string .Format(FORMAT_TRACE_PARAM, param.ParameterName, param.Value));
                    }
                }
            }
        }

         #endregion

         #region  helper

         ///   <summary>
         ///  根据日志策略生成日志
         ///   </summary>
         private   static   void  StrategyLog()
        {
             // 判断日志日期
             if  (DateTime.Compare(DateTime.Now.Date, CurrentLogFileDate.Date)  !=   0 )
            {
                DateTime currentDate  =  DateTime.Now.Date;

                 // 生成子目录
                BuiderDir(currentDate);
                 // 更新当前日志日期
                CurrentLogFileDate  =  currentDate;

                System.Diagnostics.Trace.Flush();

                 // 更改输出
                 if  (twtl  !=   null )
                    System.Diagnostics.Trace.Listeners.Remove(twtl);

                System.Diagnostics.Trace.Listeners.Add(TWTL);
            }
        }

         ///   <summary>
         ///  根据年月生成子目录
         ///   </summary>
         ///   <param name="currentDate"></param>
         private   static   void  BuiderDir(DateTime currentDate)
        {
             int  year  =  currentDate.Year;
             int  month  =  currentDate.Month;
             // 年/月
             string  subdir  =   string .Concat(year,  ' \\ ' , month);
             string  path  =  Path.Combine(log_root_directory, subdir);
             if  ( ! Directory.Exists(path))
            {
                Directory.CreateDirectory(path);
            }
            log_subdir  =  subdir;
        }

         #endregion

         #endregion

         #region  Properties

         ///   <summary>
         ///  日志文件路径
         ///   </summary>
         ///   <returns></returns>
         private   static   string  GetLogFullPath
        {
             get
            {
                 return   string .Concat(log_root_directory,  ' \\ ' ,  string .Concat(log_subdir,  @" \log " , CurrentLogFileDate.ToShortDateString(),  " .txt " ));
            }
        }

         ///   <summary>
         ///  跟踪输出日志文件
         ///   </summary>
         private   static  TextWriterTraceListener TWTL
        {
             get
            {
                 if  (twtl  ==   null )
                {
                     if  ( string .IsNullOrEmpty(log_subdir))
                        BuiderDir(DateTime.Now);
                     else
                    {
                         string  logPath  =  GetLogFullPath;
                         if  ( ! Directory.Exists(Path.GetDirectoryName(logPath)))
                            BuiderDir(DateTime.Now);
                    }
                    twtl  =   new  TextWriterTraceListener(GetLogFullPath);
                }
                 return  twtl;
            }
        }

         #endregion

    }
}

         static   void  Main( string [] args)
        {
            IList < string >  list  =   null ;

             try
            {
                Console.WriteLine(list.Count);
            }
             catch  (Exception ex)
            {
                Logger.Trace(ex);
            }

            Console.ReadLine();
        }

             using  (SqlConnection con  =   new  SqlConnection( " Data Source=OVERA;Initial Catalog=Northwind;User ID=sa;Password=sa; " ))
            {
                con.Open();
                SqlCommand sqlCmd  =   new  SqlCommand( " SELECT * FROM Customers WHERE CompanyName = @CompanyName " , con);
                sqlCmd.Parameters.Add( new  SqlParameter( " @CompanyName " ,  " Alfreds Futterkiste " ));

                Logger.Trace(sqlCmd);

                SqlDataReader sdr  =  sqlCmd.ExecuteReader();
                 while  (sdr.Read())
                {
                    Console.Write(sdr.GetName( 1 ));
                    Console.Write( "  :  " );
                    Console.WriteLine( sdr[ 1 ]); 
                }
                sdr.Close();
            }

            Console.ReadLine();
        }