LabVIEW
Reflection-like operations for VIs?
Solved!
Like Mike said, you can use a property node of the front panel to get an array of references to its controls. The property is called Controls[ ]. You can use these references to get property names, and whether they're controls or indicators rather easily.
The more tricky part is figuring out their data types. To do this, you'll need to take a few steps. First, read the Value property of the generic control reference. Since this is generic, the data type output of this property node is a Variant data type. But there are reflection functions available in vi.lib for determining the data type of data in a Variant wire.
These functions can be found at <LabVIEW>\vi.lib\Utility\VariantDataType. I haven't used them much personally, but generally you can call a function which will return an enum with the top-level data type of the data. Sometimes this is something directly useful like Boolean, and sometimes it returns something like Array or Cluster, which requires you to call an additional function to peak at the data values in the container.
It takes some leg work, but it's all there and should get you going.
Well, I've spent all day trying to get it to run. To traverse clusters, I had to emulate recursion using an array hacked into a stack 
and I can make that work since it's necessary. But now I think I've hit a brick wall.
Among all the other stuff that needs to be done to make reflection work, I need to get the names and types of the elements of a cluster. GetClusterInfo.vi does not return the names, just the types.
Is there a workaround?
Thanks,
- Steve.
Good work!
One thing that might make your life easier in the future is being able to get an enum's selected string value automatically in LabVIEW, rather than having to type a lot of string constants to put in a case structure. The trick is to use Format to String and wire in the enum value.
