Exception not thrown from FormLoad inside a WindowsFormsHost

Question

In a porting from WinForm to WPF, I setted up a WindowsFormsHost that hosts all my old Form.

I'm setting the form as child in a setter like this:

set{
  try{
    windowsFormsHost.Child = value;
  }
  catch{}
}

Then, I noticed that if the Load function of the form (value in this case) throws an exception, the function just go further and I cannot see the exception. Even if I use a try catch block, nothing happens.

How can I catch the exceptions thrown by value load?

Have you tried to debug your application? Could you please post the stack trace of the exception? Could you also provide more code context? — dymanoid, May 28 '20 at 14:29
It does not happen on a single exception: every exception is not rethrown — Emanuele, May 28 '20 at 14:32
And debugging I see the exception thrown in the load function, but the code just step on the line after the windowsFormsHost.Child = value; as nothing happened — Emanuele, May 28 '20 at 14:33
Check "Common Language Runtime Exceptions" and "Managed Debugging Assistants" in the Debug menu->Windows ->Exception Settings — Maria, May 28 '20 at 19:32

score 0 · Answer 1 · answered May 29 '20 at 12:19

0

Setting the Child property won't cause an exception to be thrown.

It gets thrown at a later stage, long after your try/catch block has been executed and the method where this code is defined has already returned.

You need to catch exceptions where they occur, i.e. inside your form in this case.

You may also define global error handlers in your app.

answered May 29 '20 at 12:19

mm8

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Unfortunately, I have a global error handler (that works when the form is loaded), but it is not triggered during this phase – Emanuele May 29 '20 at 16:10
So catch the exception in the form then? – mm8 Jun 01 '20 at 12:10

Exception not thrown from FormLoad inside a WindowsFormsHost

1 Answers1