It’s an all too common scenario when your ASP.NET page takes too long to load and the culprit is slow, long running SQL query. It shouldn’t come to this, you should optimize your DB stuff to minimize delays, but if you’re trying to decode feline genome or find alien live in the neighboring galaxies – that’s unavoidable. So the page is running and at some point you decide enough is enough and decide you need to cancel it. But you want to do it gracefully, for example slow page is in an IFRAME and you want to remain in the parent page and you don’t want to close/reload the whole thing.

There’s a way. The idea is, every time you create an SqlCommand – you add it to static (shared in VB.NET) list. If command runs successfully – you remove it from the list. But if it takes too long – you can issue an AJAX call from client page to cancel the command stored in that list.

Thanks Arsalan Tamiz for posting this solution to my question on StackOverflow. His demo project was in C# (you can download it from the above link). but since most of my projects are in VB.NET – I did a conversion with some adjustments.
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