如何在c＃中写日志文件？
我如何在c＃中编写日志文件？
目前我有一个带有此语句的计时器，每20秒计时一次：
File.WriteAllText(filePath+"log.txt", log); 对于我想要记录的所有内容，我这样做：
log += "stringToBeLogged";
您可以假设字符串日志随着程序的运行而增长和增长。 （我甚至不知道每个字符串是否有最大字符数？）
我认为必须有更好的方法来做到这一点。 我只是觉得每次将某些内容添加到日志中时，反复写入整个文件会很重。
从性能的角度来看，您的解决方案并非最佳。 每次使用+ =添加另一个日志条目时，整个字符串将被复制到内存中的另一个位置。 我建议使用StringBuilder：
StringBuilder sb = new StringBuilder(); ... sb.Append("log something"); ... // flush every 20 seconds as you do it File.AppendAllText(filePath+"log.txt", sb.ToString()); sb.Clear();
顺便说一句，你的计时器事件可能在另一个线程上执行。 因此，您可能希望在访问sb对象时使用互斥锁。
另一件需要考虑的事情是在执行的最后20秒内添加的日志条目会发生什么。 您可能希望在应用程序退出之前将字符串刷新到文件。
创建一个类全局创建一个对象并调用它
using System.IO; using System.Reflection; public class LogWriter { private string m_exePath = string.Empty; public LogWriter(string logMessage) { LogWrite(logMessage); } public void LogWrite(string logMessage) { m_exePath = Path.GetDirectoryName(Assembly.GetExecutingAssembly().Location); try { using (StreamWriter w = File.AppendText(m_exePath + "\\" + "log.txt")) { Log(logMessage, w); } } catch (Exception ex) { } } public void Log(string logMessage, TextWriter txtWriter) { try { txtWriter.Write("\r\nLog Entry : "); txtWriter.WriteLine("{0} {1}", DateTime.Now.ToLongTimeString(), DateTime.Now.ToLongDateString()); txtWriter.WriteLine(" :"); txtWriter.WriteLine(" :{0}", logMessage); txtWriter.WriteLine("-------------------------------"); } catch (Exception ex) { } } }
请改用File.AppendAllText ：
File.AppendAllText(filePath + "log.txt", log);
public static void WriteLog(string strLog) { StreamWriter log; FileStream fileStream = null; DirectoryInfo logDirInfo = null; FileInfo logFileInfo; string logFilePath = "C:\\Logs\\"; logFilePath = logFilePath + "Log-" + System.DateTime.Today.ToString("MM-dd-yyyy") + "." + "txt"; logFileInfo = new FileInfo(logFilePath); logDirInfo = new DirectoryInfo(logFileInfo.DirectoryName); if (!logDirInfo.Exists) logDirInfo.Create(); if (!logFileInfo.Exists) { fileStream = logFileInfo.Create(); } else { fileStream = new FileStream(logFilePath, FileMode.Append); } log = new StreamWriter(fileStream); log.WriteLine(strLog); log.Close(); }
参考链接： blogspot.in
非常方便的日志记录工具是http://logging.apache.org/log4net/
你也可以使自己的东西变得更少（更强大）。 您可以使用http://msdn.microsoft.com/ru-ru/library/system.io.filestream(v = vs.110）。 ASPX
使用静态类添加日志到文件
public static class LogWriter { private static string m_exePath = string.Empty; public static void LogWrite(string logMessage) { m_exePath = Path.GetDirectoryName(Assembly.GetExecutingAssembly().Location); if (!File.Exists(m_exePath + "\\" + "log.txt")) File.Create(m_exePath + "\\" + "log.txt"); try { using (StreamWriter w = File.AppendText(m_exePath + "\\" + "log.txt")) AppendLog(logMessage, w); } catch (Exception ex) { Console.WriteLine(ex.Message); } } private static void AppendLog(string logMessage, TextWriter txtWriter) { try { txtWriter.Write("\r\nLog Entry : "); txtWriter.WriteLine("{0} {1}", DateTime.Now.ToLongTimeString(),DateTime.Now.ToLongDateString()); txtWriter.WriteLine(" :"); txtWriter.WriteLine(" :{0}", logMessage); txtWriter.WriteLine("-------------------------------"); } catch (Exception ex) { } } }
有两种简单的方法
- StreamWriter – http://www.dotnetperls.com/streamwriter
- Log4Net如Log4j（Java） – http://www.codeproject.com/Articles/140911/log4net-Tutorial
由@randymohan发布，改为使用using语句
public static void WriteLog(string strLog) { string logFilePath = @"C:\Logs\Log-" + System.DateTime.Today.ToString("MM-dd-yyyy") + "." + "txt"; FileInfo logFileInfo = new FileInfo(logFilePath); DirectoryInfo logDirInfo = new DirectoryInfo(logFileInfo.DirectoryName); if (!logDirInfo.Exists) logDirInfo.Create(); using (FileStream fileStream = new FileStream(logFilePath, FileMode.Append)) { using (StreamWriter log = new StreamWriter(fileStream)) { log.WriteLine(strLog); } } }
if(!File.Exists(filename)) //No File? Create { fs = File.Create(filename); fs.Close(); } if(File.ReadAllBytes().Length >= 100*1024*1024) // (100mB) File to big? Create new { string filenamebase = "myLogFile"; //Insert the base form of the log file, the same as the 1st filename without .log at the end if(filename.contains("-")) //Check if older log contained -x { int lognumber = Int32.Parse(filename.substring(filename.lastIndexOf("-")+1, filename.Length-4); //Get old number, Can cause exception if the last digits aren't numbers lognumber++; //Increment lognumber by 1 filename = filenamebase + "-" + lognumber + ".log"; //Override filename } else { filename = filenamebase + "-1.log"; //Override filename } fs = File.Create(filename); fs.Close(); }
参考链接：
http://www.codeproject.com/Questions/163337/How-to-write-in-log-Files-in-C
这是在文件中添加新字符串
using (var file = new StreamWriter(filePath + "log.txt", true)) { file.WriteLine(log); file.Close(); }