在C＃中创建日志

Question

I am creating logs in C# by using object of ILog in log4net. I am passing two parameters 1) repository where it will create log file 2)name of log file but it is showing exception that directory is not defined and if I do it by just passing name of log file ,program runs successfully but I am unable to find the log file.

Here is my code :-

private void createLogger(string Logdirectory)
        {
            if (Directory.Exists(Logdirectory))
            {
                Log = LogManager.GetLogger( Logdirectory , LogFilename);

            }
            else
            {
                Log = LogManager.GetLogger(LogFilename);

            }
        } 

Here is console output :-

Help me find suitable way of getting logger by Ilog or by any other method except filestream

Answer 1

Read the documentation, log4net is very configurable and well documented.

Documentation: https://logging.apache.org/log4net/release/manual/configuration.html

using Com.Foo; // Import log4net classes.
using log4net;
using log4net.Config;
public class MyApp
{ // Define a static logger variable so that it references the // Logger instance named "MyApp".
  private static readonly ILog log = LogManager.GetLogger(typeof(MyApp));
  static void Main(string[] args)
  { // Set up a simple configuration that logs on the console.
   BasicConfigurator.Configure();
   log.Info("Entering application.");
   Bar bar = new Bar();
   bar.DoIt();
   log.Info("Exiting application.");
 }
}

Take note the difference in the method for getting to log instance.

1. You're asking for an ILog for the current Type not an explicitly a filename
2. You're telling log4net to read configuration settings from the app.config/web.config
3. Depending on your config you may need to use the XmlConfigurator

An example of the .config file is:

<log4net> <!-- A1 is set to be a ConsoleAppender -->
 <appender name="A1" type="log4net.Appender.ConsoleAppender"> <!-- A1 uses PatternLayout -->
  <layout type="log4net.Layout.PatternLayout"> 
   <conversionPattern value="%-4timestamp [%thread] %-5level %logger %ndc - %message%newline" />
  </layout>
 </appender>
<!-- Set root logger level to DEBUG and its only appender to A1 -->
 <root>
  <level value="DEBUG" />
  <appender-ref ref="A1" />
 </root>
</log4net>

There are lots of Appenders, above is a ConsoleAppender, but a DatabaseAppender exists and other types that might fit with you're need.