handle unhandled exception

Question

Hi all,

I have a Ria service to call logic code. I want to write try catch block in every logic funtion to provide ways to handle unhandeled exceptions.

try
{
//something
}
catch(BussinessException e)
{
//save e.info to database
}

But I don't want to write this block code everywhere in my logic, and I don't want to put the exception handling piece in RIA service since another type of service also call the logic.

Does anybody have a one-place exception handling solution for me?

Thanks a lot.

Answer 1

Based off your history I am pretty sure this is C# so here is my take.

The best way to avoid the duplication would be to wrap your logic like this.

private static void ExecuteLogic(Action action)
{
    try
    {
        action();
    }
    catch(BussinessException e)
    {
        //save e.info to database
    }
}

With this in place you can easily perform various operations that share the same error handling.

ExecuteLogic(
    () =>
    {
        // Do something...
    }
);

Answer 2

If you want only to log exception, as I can see from your example, you can subscribe to AppDomain.FirstChanceException. But you wouldn't be able to handle it. Oh. btw this event was introduces only in .NET 4 :(.

Answer 3

Here is a more conventional Object Oriented solution using Command Pattern.

public interface ICommand {
  void Execute();
}

public class BankAccountWebServiceCall: ICommand(){

  string name;
  int accountNo;

  public BankAccountWebServiceCall(string name, int accountNo) {
    this.name= param1;
    this.accountNo= accountNo;
  }

  //ICommand implementation
  public void Execute() {
    SomeWebService.Call(name, accountNo);
  }
}

public class WebServiceCaller {
  public void CallService(ICommand command) {
    try {
      command.Execute();
    } catch (SomeBusinessException ex) {
      //handle exception
    }
  }
}

public class WebServiceCallerTest {
  public static void CallServiceTest() {
    new WebServerCaller().CallService(new TwoParameterwebServiceCall("Igor", 12345));
  }
}

Answer 4

implement an IHttpModule

web.config:

<httpModules>
    ...
    <add type="Citiport.Web.Module.ErrorHandleModule" name="GlobalErrorHandler" />
    ...
</httpModules>

The Class:

public class ErrorHandleModule : IHttpModule
    {

        private static readonly ILog logger = LogManager.GetLogger("Citiport.Web.Module.ErrorHandleModule");

        public ErrorHandleModule()
        {

        }

        void IHttpModule.Dispose()
        {
        }

        void IHttpModule.Init(HttpApplication context)
        {
            context.Error += new System.EventHandler(onError);
        }

        public void onError(object obj, EventArgs args)
        {
            HttpContext ctx = HttpContext.Current;
            HttpResponse response = ctx.Response;
            HttpRequest request = ctx.Request;

            Exception exception = ctx.Server.GetLastError();
            /* handling exception here*/
        }
    }
}

refer:http://code.google.com/p/citiport2/source/browse/trunk/CitiportV2_website/App_Code/Web/ErrorHandleModule.cs