Class Library Exception Passing To Other Class Library Or Executable?

Posted on 2012-12-22
Last Modified: 2012-12-27
I want to learn the absolute correct way to pass exceptions from Class Library .dll to other .dll or Executable (Form1). I don't receive the actual .dll exception, instead I receive a general try/catch exception from the Form1 attempt to use the .dll. Help!

[Example Summary]
Click a button on Form1 to clear the local Queue without first specifying the Queue name will cause an exception.
Seems to me the the .dll CreateQueue() exception should 'bubble-up' to Form1.

Does this make sense?

Q1. How do I pass the .dll exception to the .exe (MyForm1)?
Q2. How do I pass the .dll exception to another .dll then to .exe (MyForm1)?

public static void ClearQueue()
            msgQueue.QueueName = ""; //intentionally blank for testing purposes

[MyQueueManager.dll] (referenced by MyForm1.exe)
        public static void CreateQueue()
                if (MessageQueue.Exists(_queueName))
                    msgQueue = new MessageQueue(_queueName);
                    msgQueue = MessageQueue.Create(_queueName);
            catch (MessageQueueException ex)
                throw new Exception("MsmqManager.MSMQueue.CreateQueue() Exception: ", ex);

        public static void ClearQueue()

Question by:pointeman
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
  • 3
  • 3
LVL 18

Accepted Solution

Gary Davis earned 500 total points
ID: 38715724
Since your dll is doing a throw, your call to msgQueue will need a try/catch to know the details of the exception being thrown.

Another alternative is to have an Error property within the MessageQueue class and that would have to be set with the error information if an error occurs instead of issuing a throw. Then you will need to test the Error property at various points and act as needed.

Gary Davis

Author Comment

ID: 38715761
Q. Do you think the .dll 'Catch' is correct or do you recommend another way?
LVL 18

Expert Comment

by:Gary Davis
ID: 38716052
The try/catch in the dll looks correct to me.
Independent Software Vendors: We Want Your Opinion

We value your feedback.

Take our survey and automatically be enter to win anyone of the following:
Yeti Cooler, Amazon eGift Card, and Movie eGift Card!


Author Comment

ID: 38716084
Q. Do you prefer throw ex; vs my code example?

I've also been working with throw ex.Innexcepion; as well.
LVL 18

Expert Comment

by:Gary Davis
ID: 38716224
I'm not sure I understand. Your example does issue a throw.

Author Closing Comment

ID: 38725618

Featured Post

PeopleSoft Has Never Been Easier

PeopleSoft Adoption Made Smooth & Simple!

On-The-Job Training Is made Intuitive & Easy With WalkMe's On-Screen Guidance Tool.  Claim Your Free WalkMe Account Now

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Suggested Solutions

Title # Comments Views Activity
Please explain purpose of GZIP 4 80
orderby list (from Json) 1 42
Need help with another query 10 50
How do you think this website does searches? 5 30
Introduction This article series is supposed to shed some light on the use of IDisposable and objects that inherit from it. In essence, a more apt title for this article would be: using (IDisposable) {}. I’m just not sure how many people would ge…
Entity Framework is a powerful tool to help you interact with the DataBase but still doesn't help much when we have a Stored Procedure that returns more than one resultset. The solution takes some of out-of-the-box thinking; read on!
The Email Laundry PDF encryption service allows companies to send confidential encrypted  emails to anybody. The PDF document can also contain attachments that are embedded in the encrypted PDF. The password is randomly generated by The Email Laundr…
Are you ready to implement Active Directory best practices without reading 300+ pages? You're in luck. In this webinar hosted by Skyport Systems, you gain insight into Microsoft's latest comprehensive guide, with tips on the best and easiest way…
Suggested Courses

738 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question