LabVIEW
LabView 7.1 and .NET 3.5 problems
Hello,
I am trying to add a piece of external hardware to an existing hardware/software solution built on the LabView 7.1 platform.
The new hardware is DIMAX Sub-20. I am having very inconsisent behavior from LabView 7.1 when trying to add a .NET constructor contained within the manufacturer's .NET dll. The problem is trying to add a new .NET constructor to the block diagram. When I place the icon on the diagram the "Select .NET Constructor" appears. I choose my dll and then the "object" in the window. Now SOMETIMES the constructor function appears in the "Constructors" box... sometimes it doesn't. I know the hardware's .NET dll is working because I am able to see the constructor properly in LabView 8.2.1 (see attached for behavior comparison).
I have upgraded to LV 7.1.1f2 and the behavior is still the same (erradic).
I also tried added the dll to my GAC (C:\windows\assembly) and also adding it to the same folder as the main VI. I've tried different combinations of these two and there doesn't appear to be a pattern. There are two things that are particularly strange. Once a constructor icon is down on the block diagram and I've in the past been able to select the constructor function desired, then that particular icon can be copy and pasted over and over and keeps working. However, sometimes I will try to add a new icon, same constructor function, and the function won't appear in the selection window. I then right-click on the "working" icons and now the constructor function is missing even though the VI will execute. It is like the icon is correctly linked to the hardware's .NET dll, BUT when I try to add new constructors it cannot initiate a new constructor function. The second strange part is the I can browse through the other .NET classes in my GAC and access other constructors, so I know it isn't a system-wide problem. Is there something specific to the way constructor classes must be defined or typed to be compatible with 7.1 (or 7.1.1f2 which supposedly corrected some strange .NET behavior)?
The add constructor behavior is as expected in 8.2.1, but unfortunately using it is not an option because the existing hardware/software would require a lot of modification.
Any ideas?
