>>>>When is it very large? We found that 2000 is no problem. However, 5000 or more is troublesome. Somewhat smarter coding should focus on reducing the number of objects.
>>>
>>>There you go. It's hard to imagine a proper OO design including a class with 2000 objects.
>>
>>Is it, Mike ?
>
>Forget Mike, he openly confesses problems with his imagination :).
>
>Actually, when the requirements are such, a good OOP design is perhaps the only way to have that many objects efficiently organized.
>
>An afterthought - if form destruction is so slow (but by now we see Peter has reduced the problem to manageable sizes), perhaps hidden destruction would work. Hide the form, stop its code, then fire a timer and slowly release the objects at some lower level, one container at a time.

This type of solution was already proposed by someone here. But it requires a modeless form. One might in that case even consider a design where the form isn't destroyed at all, but rather made invisible until it is reused for a next case.