如何处理WCF服务回调中的异常

Question

I am trying to log my exceptions with AppDomain.CurrentDomain.UnhandledException.

AppDomain.CurrentDomain.UnhandledException += AppDomainUnhandledException;
public static void AppDomainUnhandledException(object sender, UnhandledExceptionEventArgs e)
{
        HandleException(e.ExceptionObject as Exception);
}

When I get an exception in the server I will get the fault in the client at debug time but the event hooked to AppDomain.CurrentDomain.UnhandledException will never be fired.

Server:

[ServiceBehavior(IncludeExceptionDetailInFaults=true)]
public class Service : IService
{        

    public string GetError()
    {
       throw new ApplicationException();
    }
}

Client:

public void GetError()
{
   this.service.BeginGetError(OnGetErrorCompleted, null);
}

public void OnGetErrorCompleted(IAsyncResult result)
{ 
    var value = this.service.EndGetError(result);
}

This doesn't work UNLESS I use Distpacher.BeginInvoke..

public void OnGetErrorCompleted(IAsyncResult result)
{
    this.Dispatcher.BeginInvoke((Action)(() =>
    {
        var value = this.service.EndGetError(result);
    }));           
}

Somebody knows why?? I thought AppDomain.CurrentDomain.UnhandledException would be fired in case of an exception in ANY thread! :S

Answer 1

A better solution is to use something like IErrorHandler and throw FaultExceptions. Decorate your operations to throw FaultExceptions using the FaultContract attribute. Now you can catch specific FaultExceptions at the client. You should not expose exceptions on the server to the client.