Custom error handeling and log

For log4Net:
How to use log4net[^]
Log4Net Tutorial in C# .net [^]

If needed, look here[^] for more.


For Microsoft Enterprise Library - Logging Application block:
Introduction to the Logging Application Block[^]
Getting started with the Logging Application Block[^]


While providing you the link, came across this discussion[^] that differentiates and tells the advantages of them in detail.

What you want is not possible (as far as I know).

All you can do is trapping the uncought exceptions:

static class Program
{
    [STAThread]
    static void Main()
    {
       ...
       //Exceptions from main thread
       Application.ThreadException += new ThreadExceptionEventHandler(UIThreadUnhandledException);
       Application.SetUnhandledExceptionMode(UnhandledExceptionMode.CatchException);
       //Exceptions from other threads
       AppDomain.CurrentDomain.UnhandledException +=
           new UnhandledExceptionEventHandler(OtherThreadUnhandledException);
       ...
    }

    // This function is called if an exception was raised from the main thread and was not handled.
    // Your program can still continue after such an error.
    private static void UIThreadUnhandledException(object sender, ThreadExceptionEventArgs t)
    {
        ...
    }
    // This function is called if an exception was raised from another thread and was not handled
    // Your program can't continue after such an error: the framework will close it.
    private static void OtherThreadUnhandledException(object sender, UnhandledExceptionEventArgs e)
    {
       ...
    }

See here http://msdn.microsoft.com/en-us/library/ms733025.aspx[^] where it states all exceptions are logged if trace level is set to error.

The only way I know of to handle your 'override catch problem' in code is to rethrow the error from the catch so that your global error handler can catch it.
However if you attach a debugger, you can set the debugger to break when any exception is thrown.
In VS2010, this option is located in Debug->Exceptions (ctrl-alt-e)

Edit:

kia.sos wrote:

In other words, consider try ... catch ... finally structure similar to other
application events and override catch section, run our custom code next run
catch section code.

AFAIK, there is no way to run your catch first since exception propagate via bubbling not tunneling.
You could try coding your own trace listener and 'handle' the exception when the tracer receives it. However, I do not know if the tracer or the user's catch statement would be the first to be executed.