API Guide
Sooner or later, every VB programmer needs to be able to plugin to the native Windows framework to perform some task which isn't possible with their development platform. The KPD-Team from Belgium, offers a nicely documented and searchable database of over 900 useful functions which make up the API-Guide:

So, if (like us) you're still occasionally having to support applications which haven't been migrated to the .NET Framework, you'll find the API-Guide an indispensable starting point to programmatically accessing the Windows user interface, network communications, numeric algorithms, data access, cryptography and more.
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