文件日志类FileLogHelper

该类主要用于对程序进行跟踪，记录程序运行过程，便于查找问题所在。

    /// <summary>
    /// 文件日志类
    /// </summary>
    public class FileLogHelper
    {
        private static FileLogHelper _instance;
        private static readonly object lockObject = new object();

        private bool IsEnabledLog = true; // 是否启用日志功能
        private bool IsRecordStackInfo = true; // 是否记录堆栈信息
        private long fileMaxLenth; // 日志文件的最大长度(字节)
        private FileStream fs;
        private string filePath;

        /// <summary>
        /// 单例模式
        /// </summary>
        public static FileLogHelper Instance
        {
            get
            {
                lock (lockObject)
                {
                    if (_instance == null)
                    {
                        _instance = new FileLogHelper();
                    }
                    return _instance;
                }
            }
        }


        /// <summary>
        /// 加载配置文件信息
        /// </summary>
        private FileLogHelper()
        {
            NameValueCollection appSettings = System.Configuration.ConfigurationManager.AppSettings;
            string isEnabled = appSettings["LogIsEnabled"];
            string isRecordStack = appSettings["IsRecordStack"];
            string maxLimit = appSettings["LogFileMaxLimit"];

            bool enabled;
            if (bool.TryParse(isEnabled, out enabled))
            {
                IsEnabledLog = enabled;
            }
            else
            {
                IsEnabledLog = true; // 默认启用日志功能
            }

            bool recordStack;
            if (bool.TryParse(isRecordStack, out recordStack))
            {
                IsRecordStackInfo = recordStack;
            }
            else
            {
                IsRecordStackInfo = true; // 默认记录堆栈信息
            }

            int fileMaxLimit, max;
            if (int.TryParse(maxLimit, out max))
            {
                fileMaxLimit = Math.Max(5, max); // 限制最小5M
                fileMaxLimit = Math.Min(20, max); // 限制最大20M
            }
            else
            {
                fileMaxLimit = 10; // 默认20M
            }
            fileMaxLenth = fileMaxLimit * 1024 * 1024;

            filePath = GetLogFilePath();
            fs = new FileStream(filePath, FileMode.Append, FileAccess.Write);
        }

        /// <summary>
        /// 记录文件日志
        /// </summary>
        /// <param name="content">日志内容</param>
        public void Log(string content)
        {
            if (!IsEnabledLog || string.IsNullOrWhiteSpace(content))
            {
                return;
            }

            StringBuilder sb = new StringBuilder();
            sb.Append("-----------------------------------------------------------------------------------\r\n");
            sb.AppendFormat("【时间】{0}\r\n", DateTime.Now.ToString("HH:mm:ss"));
            if (IsRecordStackInfo)
            {
                sb.Append("【堆栈信息】\r\n");
                #region 获取堆栈信息
                StackTrace trace = new StackTrace(true);
                StackFrame[] frames = trace.GetFrames();
                int maxLenth = frames.Select(c => c.GetMethod().Name.Length).Max();
                int tabNum = (maxLenth + 7) / 8;
                sb.Append("\t方法");
                //并行计算
                Parallel.For(0, tabNum, (i) => { sb.Append("\t"); });
                sb.Append("行号\t列号\t文件\r\n");
                foreach (StackFrame frame in frames)
                {
                    sb.AppendFormat("\t{0}", frame.GetMethod().Name);
                    int num = (int)Math.Ceiling((decimal)(tabNum * 8 - frame.GetMethod().Name.Length) / 8);
                    //并行计算
                    Parallel.For(0, num, (i) => { sb.Append("\t"); });
                    sb.AppendFormat("{0}\t{1}\t{2}\r\n", frame.GetFileLineNumber(), frame.GetFileColumnNumber(), frame.GetFileName());
                }
                #endregion
            }
            sb.Append("【内容】\r\n\t" + content + "\r\n\r\n");

            byte[] data = System.Text.Encoding.UTF8.GetBytes(sb.ToString()); // Encoding.GetBytes(string s); s必须实例化
            fs.Write(data, 0, data.Length);

            FileInfo fi = new FileInfo(filePath);
            if (fi.Length >= fileMaxLenth)
            {
                filePath = GetLogFilePath();
                fs = new FileStream(filePath, FileMode.Append, FileAccess.Write);
            }
        }

        /// <summary>
        /// 取得当前所应操作的日志文件的路径
        /// </summary>
        /// <returns></returns>
        public string GetLogFilePath()
        {
            string strFilePath = string.Empty;
            string strYearMonthDay = DateTime.Now.ToString("yyyyMMdd");
            string logSavePath = string.Format("{0}\\log", System.AppDomain.CurrentDomain.BaseDirectory.TrimEnd("\\".ToCharArray()));
            // 判断日志保存目录是否存在，不存在则新建
            if (!System.IO.Directory.Exists(logSavePath))
            {
                System.IO.Directory.CreateDirectory(logSavePath);
            }

            //判断当天是否已有日志文件 
            string[] strFilesArray = Directory.GetFiles(logSavePath, "log_" + strYearMonthDay + "_*.txt");
            if (strFilesArray.Length == 0)
            {
                strFilePath = string.Format("{0}\\log_{1}_1.txt", logSavePath, strYearMonthDay);

                //之前没有当日的日志文件，则需要新建 
                using (File.CreateText(strFilePath))
                {

                }
            }
            else
            {
                int maxOrder = 1, fileOrder;
                string fileName = null;

                #region 获取编号最大的日志文件
                for (int i = 0; i < strFilesArray.Length; i++)
                {
                    fileName = strFilesArray[i].Trim();
                    fileName = fileName.Substring(fileName.LastIndexOf('_') + 1);
                    fileName = fileName.Replace(".txt", "");
                    fileOrder = Convert.ToInt32(fileName);
                    if (fileOrder > maxOrder)
                    {
                        maxOrder = fileOrder;
                    }
                }
                #endregion

                strFilePath = string.Format("{0}\\log_{1}_{2}.txt", logSavePath, strYearMonthDay, maxOrder);
                //判断最新文件(即编号最大)是否超容 
                FileInfo fileInfo = new FileInfo(strFilePath);
                if (fileInfo.Length >= fileMaxLenth)
                {
                    //超容了,则新建之
                    int newOrder = maxOrder + 1;
                    strFilePath = string.Format("{0}\\log_{1}_{2}.txt", logSavePath, strYearMonthDay, newOrder);
                    using (File.CreateText(strFilePath))
                    {

                    }
                }
            }
            return strFilePath;
        }

        /// <summary>
        /// /获取指定文件夹的大小 
        /// </summary>
        /// <param name="dir">目录实例</param>
        /// <returns></returns>
        public static long FolderSize(System.IO.DirectoryInfo dir)
        {
            if (dir == null || !dir.Exists)
            {
                return 0;
            }
            long size = 0;
            FileInfo[] files = dir.GetFiles();
            foreach (System.IO.FileInfo info in files)
            {
                size += info.Length;
            }
            DirectoryInfo[] dirs = dir.GetDirectories();
            foreach (DirectoryInfo dirinfo in dirs)
            {
                size += FolderSize(dirinfo);
            }
            return size;
        }
    }

需要在配置文件中进行配置的项：

<?xml version="1.0" encoding="utf-8" ?>
<configuration>
  <appSettings>
    <!--是否启用日志记录功能，默认为true-->
    <add key="LogIsEnabled" value="true"/>
    <!--是否同时记录堆栈信息(文件,方法,行号,列号)，默认为true-->
    <add key="IsRecordStack" value="true"/>
    <!--单个日志文件的最大限制(单位：MB)，默认为10(范围[5-20])-->
    <add key="LogFileMaxLimit" value="10"/>
  </appSettings>
</configuration>

方法调用：

FileLogHelper.Instance.Log(DateTime.Now.ToString("yyyy-MM-dd HH:mm:ss"));

运行结果：
-----------------------------------------------------------------------------------
【时间】11:48:27
【堆栈信息】
 方法　　　　行号　　 列号　　 文件
 Log  　　　 106 　   17 　　  E:\QvodVideoCombiner\QvodVideoCombiner\FileLogHelper.cs
 FileCreate  30　　   17　　   E:\QvodVideoCombiner\QvodVideoCombiner\Program.cs
 Main 　　   23　　   13　　   E:\QvodVideoCombiner\QvodVideoCombiner\Program.cs
【内容】
 2013-01-18 48:27 测试一下:0)