Callbacks and VB

[dnsholliday]

I need to know if callbacks are supported in VB. Knowledge Base ID:117AR84S indicates that as of VB5.0 callbacks are supported, however, the NI_VISA3.2 users manual continues to state that they aren't and only gives examples of using queues. Searching the developers zone gives a lot of info about LaBView, C++ and TestStand, nothing could be found specifically about VB.

Can anyone tell me if callbacks are supported in VB6.0 and NI-VISA3.2, and if they are, are there any programming examples available?


Thanks.

[Julianna]

Hello!

Using the NI-VISA Type Library to do VB 5.0 callbacks is very complex. You cannot pass function pointers because there are no functions in VB, using visa32.bas. We do not have examples using NI-VXI 3.2 and VB callbacks.

NI-VISA COM and Component Works for Visual Basic are the recommended environments for using callbacks with VB. NI-VISA COM is a part of NI-VISA 2.6, and uses the COM standard. NI-VISA 2.6 does not yet document this API, so only those developers familiar with the specification should use it in this release. Component Works for VB is much more documented with more examples.