Martin Martin - 3 months ago 25
C# Question

How to prevent Debug.Assert(...) to show a modal dialog

I have a couple of libraries which use Debug.Assert(...). I think that the Debug.Assert(...) are fine and I still want them to execute, but I don't want them to block the execution of my application. Ideally, I would only like them to be logged somewhere.

Given that I can't change the code of the libraries (and that I still want to compile in debug and run the assertion), how do I prevent Debug.Assert(...) to show a modal dialog?

In addition, I would like to make sure that the main program continues when an Assert occurs (same behaviour as the Ignore button).



I wouldn't recommend it. The problem is that Debug.Assert is only supposed to be fired when you have bugs in your code. If you just ignore them or don't fix them, then you are doing your users a disservice. If, on the other hand, you're firing Debug.Assert for things that aren't bugs, then you're also doing your users a disservice (by reducing the impact of Debug.Assert).

Having said that, you can disable it. The first thing you need to do is remove the default listener from the Debug.Listeners collection:


Then, add your own instead:

Debug.Listeners.Add(new MyTraceListener());

You need to create a class that inherits from TraceListener:

class MyTraceListener : TraceListener
    // ...

    public override void Fail(string msg, string detailedMsg)
        // log the message (don't display a MessageBox)

The important method is the TraceListener.Fail method, which in the implementation of DefaultTraceListener is what displays the message box.