public class MyLog { public static void WriteLog(string error) { WriteLog(error, null); } public static void WriteLog(string error, Exception ex) { string dir = Application.StartupPath + "\\LOG"; if (!Directory.Exists(dir)) { Directory.CreateDirectory(dir); } error = DateTime.Now.ToString() + " " + error + System.Environment.NewLine; if (ex != null) { error += ex.ToString() + System.Environment.NewLine; } string logFilePath = dir + "\\log_" + DateTime.Now.ToString("yyyy-MM-dd") + ".log"; File.AppendAllText(logFilePath, error); } }