Hi
First, thanks for replying me.

now that is working.
but now i wanna know, Should this piece of code be written  in constructor
of each class i write.

      FileInfo log4NetConfigFile = new FileInfo("log4net.config");

  if (log4NetConfigFile == null || !log4NetConfigFile.Exists) throw new
Exception("unable to find log file");

log4net.Config.XmlConfigurator.ConfigureAndWatch(log4NetConfigFile);

thank you
wijitha

At the program or service entry point.

Without a hard path, you will want it in the bin/debug and bin/release
folder for your dev environment.
There is the chicken and egg issue of providing a path for it in the config
file - do you want to record config problems, etc.?