Please note that you won't be able to catch such an exception with the type from within the application, e.g.:

=== code begin ===

try
  SomeLibraryFunction;
except
  on e: TMyObject do
     Whatever;
  else
     WhateverElse;
end;

=== code end ===

The above code would go to the first branch *inside* your library, but it will *always* go to the else-branch outside your library, cause the comparison is done on the pointer to the VMT (the class type) which will be *different* between library and application (even if you use the same unit!). This is one of the main reasons why dynamic packages are needed for comfortable use of libraries in Object Pascal, because it allows such types to be shared across module boundaries.

My situation is even worser :-)
Library DLL is writen in Pascal, but main application is C/C#.

Then it will probably be caught as some external exception or such... don't know, never tried it.
*“System.Runtime.InteropServices.SEHException (0x80004005): External component has thrown an exception.”*


When I call in library RunError() then whole application aborts.
I need throw exception in library which can be catched in application.

I now use in unit which is used by library:

  if System.IsLibrary then
    raise TObject.Create // raise exception - type of exception is not important ...     // can I call here also Windows's RaiseException()? ... so it will be propagated to linking application?
  else
    System.RunError(w);

"raise" internally uses . The only difference would be that you'd have a bit more control of exception code and such if you want to ensure that it's caught nicely by the C/C++/C# code.

Ok, then if raise TObject.Create; calls RaiseException then I think that I will use raise TObject.Create;
Thanks
L.*
*
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