日志类 LogUtil

本文转载：http://www.cnblogs.com/HopeGi/archive/2012/12/31/2840812.html

using System;
 using System.IO;
 
 namespace Common
 {
     /// <summary>
     /// 日志类
     /// </summary>
     public static class LogUtil
     {
         /// <summary>
         /// 配置默认路径
         /// </summary>
         private static string defaultPath = System.Configuration.ConfigurationManager.AppSettings["logPath"];
 
         #region Exception异常日志
 
         /// <summary>
         /// 写异常日志，存放到默认路径
         /// </summary>
         /// <param name="ex">异常类</param>
         public static void WriteError(Exception ex)
         {
             WriteError(ex, defaultPath);
         }
 
         /// <summary>
         /// 写异常日志，存放到指定路径
         /// </summary>
         /// <param name="ex">异常类</param>
         /// <param name="path">日志存放路径</param>
         public static void WriteError(Exception ex, string path)
         {
             string errMsg = CreateErrorMeg(ex);
             WriteLog(errMsg, path, LogType.Error);
         }
 
         #endregion
 
         #region 普通日志
 
         /// <summary>
         /// 写普通日志，存放到默认路径，使用默认日志类型
         /// </summary>
         /// <param name="msg">日志内容</param>
         public static void WriteLog(string msg)
         {
             WriteLog(msg, LogType.Info);
         }
 
         /// <summary>
         /// 写普通日志，存放到默认路径，使用指定日志类型
         /// </summary>
         /// <param name="msg">日志内容</param>
         /// <param name="logType">日志类型</param>
         public static void WriteLog(string msg, LogType logType)
         {
             WriteLog(msg, defaultPath, logType);
         }
 
         /// <summary>
         /// 写普通日志，存放到指定路径，使用默认日志类型
         /// </summary>
         /// <param name="msg">日志内容</param>
         /// <param name="path">日志存放路径</param>
         public static void WriteLog(string msg, string path)
         {
             WriteLog(msg, path, LogType.Info);
         }
 
         /// <summary>
         /// 写普通日志，存放到指定路径，使用指定日志类型
         /// </summary>
         /// <param name="msg">日志内容</param>
         /// <param name="path">日志存放路径</param>
         /// <param name="logType">日志类型</param>
         public static void WriteLog(string msg, string path, LogType logType)
         {
             string fileName = path.Trim('\\')+"\\"+CreateFileName(logType);
             string logContext = FormatMsg(msg,logType);
             WriteFile(logContext, fileName);
         }
 
         #endregion
 
         #region 其他辅助方法
 
         /// <summary>
         /// 写日志到文件
         /// </summary>
         /// <param name="logContext">日志内容</param>
         /// <param name="fullName">文件名</param>
         private static void WriteFile(string logContext, string fullName)
         {
             FileStream fs = null;
             StreamWriter sw = null;
 
             int splitIndex = fullName.LastIndexOf('\\');
             if (splitIndex == -1) return;
             string path = fullName.Substring(0, splitIndex);
             
             if (!Directory.Exists(path)) Directory.CreateDirectory(path);
 
             try
             {
                 if (!File.Exists(fullName)) fs = new FileStream(fullName, FileMode.CreateNew);
                 else fs = new FileStream(fullName, FileMode.Append);
 
                 sw = new StreamWriter(fs);
                 sw.WriteLine(logContext);
             }
             finally
             {
                 if (sw != null)
                 {
                     sw.Close();
                     sw.Dispose();
                 }
                 if (fs != null)
                 {
                     fs.Close();
                     fs.Dispose();
                 }
             }
         }
 
         /// <summary>
         /// 格式化日志，日志是默认类型
         /// </summary>
         /// <param name="msg">日志内容</param>
         /// <returns>格式化后的日志</returns>
         private static string FormatMsg(string msg)
         {
             return FormatMsg(msg, LogType.Info);
         }
 
         /// <summary>
         /// 格式化日志
         /// </summary>
         /// <param name="msg">日志内容</param>
         /// <param name="logType">日志类型</param>
         /// <returns>格式化后的日志</returns>
         private static string FormatMsg(string msg, LogType logType)
         {
             string result;
             string header = string.Format("[{0}][{1} {2}] ", logType.ToString(), DateTime.Now.ToShortDateString(),DateTime.Now.ToShortTimeString());
             result= header + msg;
             return result;
         }
 
         /// <summary>
         /// 从异常类中获取日志内容
         /// </summary>
         /// <param name="ex">异常类</param>
         /// <returns>日志内容</returns>
         private static string CreateErrorMeg(Exception ex)
         {
             string result = string.Empty;
             result += ex.Message+"\r\n";
             result += ex.StackTrace+"\r\n";
             return result;
         }
 
         /// <summary>
         /// 生成日志文件名
         /// </summary>
         /// <param name="logType">日志类型</param>
         /// <returns>日志文件名</returns>
         private static string CreateFileName(LogType logType)
         {
             string result = DateTime.Now.ToString("yyyy-MM-dd");
             if (logType != LogType.Info)
                 result = logType.ToString() + result+".log";
             return result;
         }
 
         #endregion
     }
 
     /// <summary>
     /// 日志类型
     /// </summary>
     public enum LogType
     { 
         Error,
         Info,
         Option
     }
 }