I’ve just spent a useless morning surfing trying to find out where the CLASSID parameter of a VBSCRIPT OBJECT tag comes from. The most useful documentation said it comes “straight from the registry” but how do I find out what a given class id is?A VBPJ article referenced the Automatic Control Insertion Device (ACID) but I can’t find any documentation on that either.
The value of the CLASSID parameter is actually assigned to a control by Microsoft. That’s how they ensure that each CLASSID for each control will be unique. If you are using the ActiveX Control Pad, it knows how to read the CLASSID from each control and add it to your VBScript/ActiveX code. However, there is no deep, hidden meaning behind the numbers — they are essentially arbitrary.
In cases where you are creating new controls with the Control Creation Edition, it automatically assigns numbers from a particular group, since obviously you are not going to call Microsoft to find out your number. I have yet to find a good definition, but basically it is an arbitrary number.