I am using Property Nodes to set some controls, mainly to get the "data flow" feature using the error line: as most of my VIs have the error line running through them, I can ensure the control value changes after MyVI by simply wiring the ErrorOut from MyVI into the ErrorIn of the control's property node. However, I found a "feature" that (so far) I have not seen documented -- if there is an "error" on the Error line, the value will not update! This came as a complete surprise to me, as there is no "intuitive" (or "obvious") reason for me to expect that an error would prevent a control from updating or allowing any of its properties to change. I am aware of the arguments that "updating controls using property nodes" is "bad" (because it can be slow) -- however, having it inexplicably "not work" is (to my way of thinking) an even more important reason to avoid this practice! Time to dive into my VIs ... Bob Schor P.S. -- I'm attaching a picture of a very simple VI that demonstrates this. Note I've only tested this with a Boolean control. Also, I should mention I'm running Version 8.5.

LabVIEW

Indeed. My mistake!

And yes, I did test it before posting, but I now realize there was a big flaw in my test. Thanks for pointing that out!

Jarrod S.
National Instruments

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