为App添加Log日志文件

using System;
using System.Globalization;
using System.IO;
using System.Text;
using System.Windows.Forms;

namespace app.Lib
{
    public enum Level
    {
        Debug,
        Exception,
        Info,
        Warn,
    }

    public enum Priority
    {
        None,
        High,
        Medium,
        Low,
    }
    public class Logger
    {
        private static StreamWriter _writer;
        //private static string _format = "{1}: {2}. Priority: {3}. Timestamp:{0:u}";
        private static string _format = "{0:u}:{1:D3}  {2}:   {3}";
        private static StreamWriter Writer
        {
            get
            {
                if (_writer == null)
                {
                    string path = Application.StartupPath + "//Log//" + DateTime.Now.ToString("yyyy") + "//" +
                          DateTime.Now.ToString("yyyyMM") + "//" + DateTime.Now.ToString("yyyyMMddHHmmss") + ".log";
                    string filepath = Application.StartupPath + "//Log//" + "//bmp//";

                    string dir = Path.GetDirectoryName(path);
                    string filedir = Path.GetDirectoryName(filepath);

                    if (filedir != null && !Directory.Exists(filedir))
                    {
                        Directory.CreateDirectory(filedir);
                    }

                    if (dir != null && !Directory.Exists(dir))
                    {
                        Directory.CreateDirectory(dir);
                    }
                    _writer = new StreamWriter(path, true, Encoding.Default);
                    _writer.AutoFlush = true;
                }
                return _writer;
            }
        }

        public static string GetFileDirName()
        {
            return Application.StartupPath + "//Log" + "//bmp//";
        }

        public static void Log(string message, Level level)
        {
            string messageToLog = String.Format(CultureInfo.InvariantCulture, _format, DateTime.Now, DateTime.Now.Millisecond,
                level.ToString().ToUpper(CultureInfo.InvariantCulture), message);

            Writer.WriteLine(messageToLog);
        }

        public static bool EnableLog;
    }
}

很多时候需要为我们应用程序添加日子文件，方便问题定位

代码转载而来，非原创

 using System;
 using System.Collections.Generic;
 using System.Linq;
 using System.Text;
 using System.IO;
 using System.Reflection;

 namespace CommonLib
 {
     /// <summary>
     /// 日志类型
     /// </summary>
     public enum LogType
     {
         All,
         Information,
         Debug,
         Success,
         Failure,
         Warning,
         Error
     }

     public class Logger
     {

         #region Instance
         private static object logLock;

         private static Logger _instance;

         private static string logFileName;
         private Logger() { }

         /// <summary>
         /// Logger instance
         /// </summary>
         public static Logger Instance
         {
             get
             {
                 if (_instance == null)
                 {
                     _instance = new Logger();
                     logLock = new object();
                     //logFileName = Guid.NewGuid() + ".log";
                     logFileName = DateTime.Now.Hour.ToString("") + DateTime.Now.Minute.ToString("") +DateTime.Now.Second.ToString("") + ".log";
                 }
                 return _instance;
             }
         }
         #endregion

         /// <summary>
         /// Write log to log file
         /// </summary>
         /// <param name="logContent">Log content</param>
         /// <param name="logType">Log type</param>
         public void WriteLog(string logContent, LogType logType = LogType.Information, string fileName = null)
         {
             try
             {
                 string basePath = Path.GetDirectoryName(Assembly.GetExecutingAssembly().Location);
                 basePath = Directory.GetCurrentDirectory(); //@"C:\APILogs";
                 if (!Directory.Exists(basePath + "\\Log"))
                 {
                     Directory.CreateDirectory(basePath + "\\Log");
                 }

                 string dataString = DateTime.Now.ToString("yyyy-MM-dd");
                 if (!Directory.Exists(basePath + "\\Log\\" + dataString))
                 {
                     Directory.CreateDirectory(basePath + "\\Log\\" + dataString);
                 }

                 string[] logText = new string[] { DateTime.Now.ToString("hh:mm:ss") + ": " + logType.ToString() + ": " + logContent };
                 if (!string.IsNullOrEmpty(fileName))
                 {
                     fileName = fileName + "_" + logFileName;
                 }
                 else
                 {
                     fileName = logFileName;
                     //fileName = DateTime.Now.ToString("hh:mm:ss");
                 }

                 lock (logLock)
                 {
                     File.AppendAllLines(basePath + "\\Log\\" + dataString + "\\" + fileName, logText);
                 }
             }
             catch (Exception) { }
         }

         /// <summary>
         /// Write exception to log file
         /// </summary>
         /// <param name="exception">Exception</param>
         public void WriteException(Exception exception, string specialText = null)
         {
             if (exception != null)
             {
                 Type exceptionType = exception.GetType();
                 string text = string.Empty;
                 if (!string.IsNullOrEmpty(specialText))
                 {
                     text = text + specialText + Environment.NewLine;
                 }
                 text = "Exception: " + exceptionType.Name + Environment.NewLine;
                 text += "               " + "Message: " + exception.Message + Environment.NewLine;
                 text += "               " + "Source: " + exception.Source + Environment.NewLine;
                 text += "               " + "StackTrace: " + exception.StackTrace + Environment.NewLine;
                 WriteLog(text, LogType.Error);
             }
         }

     }
 }

 using System;
 using System.Collections.Generic;
 using System.Linq;
 using System.Text;
 using System.IO;
 using System.Reflection;

 namespace CommonLib
 {
     /// <summary>
     /// 日志类型
     /// </summary>
     public enum LogType
     {
         All,
         Information,
         Debug,
         Success,
         Failure,
         Warning,
         Error
     }

     public class Logger
     {

         #region Instance
         private static object logLock;

         private static Logger _instance;

         private static string logFileName;
         private Logger() { }

         /// <summary>
         /// Logger instance
         /// </summary>
         public static Logger Instance
         {
             get
             {
                 if (_instance == null)
                 {
                     _instance = new Logger();
                     logLock = new object();
                     //logFileName = Guid.NewGuid() + ".log";
                     logFileName = DateTime.Now.Hour.ToString("") + DateTime.Now.Minute.ToString("") +DateTime.Now.Second.ToString("") + ".log";
                 }
                 return _instance;
             }
         }
         #endregion

         /// <summary>
         /// Write log to log file
         /// </summary>
         /// <param name="logContent">Log content</param>
         /// <param name="logType">Log type</param>
         public void WriteLog(string logContent, LogType logType = LogType.Information, string fileName = null)
         {
             try
             {
                 string basePath = Path.GetDirectoryName(Assembly.GetExecutingAssembly().Location);
                 basePath = Directory.GetCurrentDirectory(); //@"C:\APILogs";
                 if (!Directory.Exists(basePath + "\\Log"))
                 {
                     Directory.CreateDirectory(basePath + "\\Log");
                 }

                 string dataString = DateTime.Now.ToString("yyyy-MM-dd");
                 if (!Directory.Exists(basePath + "\\Log\\" + dataString))
                 {
                     Directory.CreateDirectory(basePath + "\\Log\\" + dataString);
                 }

                 string[] logText = new string[] { DateTime.Now.ToString("hh:mm:ss") + ": " + logType.ToString() + ": " + logContent };
                 if (!string.IsNullOrEmpty(fileName))
                 {
                     fileName = fileName + "_" + logFileName;
                 }
                 else
                 {
                     fileName = logFileName;
                     //fileName = DateTime.Now.ToString("hh:mm:ss");
                 }

                 lock (logLock)
                 {
                     File.AppendAllLines(basePath + "\\Log\\" + dataString + "\\" + fileName, logText);
                 }
             }
             catch (Exception) { }
         }

         /// <summary>
         /// Write exception to log file
         /// </summary>
         /// <param name="exception">Exception</param>
         public void WriteException(Exception exception, string specialText = null)
         {
             if (exception != null)
             {
                 Type exceptionType = exception.GetType();
                 string text = string.Empty;
                 if (!string.IsNullOrEmpty(specialText))
                 {
                     text = text + specialText + Environment.NewLine;
                 }
                 text = "Exception: " + exceptionType.Name + Environment.NewLine;
                 text += "               " + "Message: " + exception.Message + Environment.NewLine;
                 text += "               " + "Source: " + exception.Source + Environment.NewLine;
                 text += "               " + "StackTrace: " + exception.StackTrace + Environment.NewLine;
                 WriteLog(text, LogType.Error);
             }
         }

     }
 }