Check if subVI is executable before actually executing it

[Sebastian.Weber]

I have a process chain where each process is a SubVI, and a main VI calls them one after one via open VI reverence -> Method "Run VI" (I don't know the exact english names)

This works great, since I can easily add new steps or change the order of steps.

However, during development it often happens that a SubVI is not executable e.g. due to an open connection. And it is a bit nasty to find this out while running the (time consuming) process chain.

I already check if the SubVI files exist, but is there a way to check if they are executable without actually executing them?

This example DOES EXECUTE the VIs, if possible:

[GerdW · Accepted solution]

Hi Sebastian,

create a new VI called "VI Tree.vi" in your project.

Drag&Drop all of your "subVIs" into this VI.

When the "VI Tree" is executable all of your subVIs are executable.

Do this ALWAYS before distributing your code.

As a responsible programmer you do only distribute tested code, don't you?

Btw. there is a property "Execution.State" (deutsch: "Ausführung.Status") of the VI. This one says "bad" when the VI is not executable…

[Sebastian.Weber]

Hi Gerd!

Well, the VI Tree has the disadvantage that the developer has to remember to add every single independent VI, and it is easy to forget one. Plus, who has a look at that VI Tree each time he touched one of the SubVIs? Maybe before deployment, but while development?

But in general I of course make VI Trees, since they also give a neat overview of a library etc.

However, the Execution.Status does the trick, and in principle, one could create a test tool checking every single VI in a directory. Thanks for that!

[GerdW]

Hi Sebastian,

the VI Tree has the disadvantage that the developer has to remember…

That's why I wrote "responsible programmer"… 😄