BartSchroder

I need help on the process of going from a built .net interop assembly DLL to using it in C#. I have built a driver for our signal acquisition hardware in Labview. I can build a DLL using Labview, and then call this DLL in MS Visual Basic, C# and C++ in the 32 bit programming environment without problems. However, when I try to call the DLL from C#, under Win 7 x64, the C# application hangs while I am in debug mode. While in release mode the application runs fine. Some more sleuthing, and it turns out that Microsoft VS C# does not support debugging under x64 when using unmanaged DLL's. (Ones called using System.Runtime.InteropServices, and the DLLImport method). The solution appears to be use of a managed .net assembly instead. Now, using Labview 2009 you can produce a .net interop assembly (Labview 2010 has a problem, and there is a CAR for it). First I created an object based wrapper for the existing VI code base by creating a Class with storage for each of the properties needed, and then writing the methods to read and write the properties, calling the existing vi codebase in the background where needed. I compiled this as a .net interop assembly. One concern is that I do not know what a 'Manifest' is, and could find no useful information on how to create one. (I'm thinking the manifest should use XML to list the class and the properties, and any help would be appreciated). So I didn't include one. Now comes the other part of the equation - how to use it in MS Visual C# (I'm using 2010). This is where I got bogged down. I know how to include standard DLL's, but not the DLL produced by Labview 2009 as a .net interop assembly DLL. I've spent a lot of time searching to no avail. I do know that an assenbly can be used either in the Global Application Store, or locally. I'm trying for local right now. My problem is nuts and bolts - what are the actual lines of code I have to write to use the assembly, and declare the properties and methods inside it to the C# program. If anyone could help with a really simple example such as a class with one method X = A+B, build an interop assembly in LV 2009 for it, and then use it in a C# project to add two numbers and display the result would be fantastic. Thanks very much - Bart

QUOTE (Michael_Aivaliotis @ Oct 28 2004, 08:37 AM) There is a problem with the NI UDP primitives. UDP Write expects a TCP Reference, while all the other UDP primitives expect a UPD Reference. So you can't wire UDP Open to UDP write. This is crazy. Anyone know the solution? Thanks.

I use app builder to build application installers that then get downloaded via the web. The installer size has been steadily growing. With the exact same code I find the LV6.1 installer is 10 Mbyte, LV7.0 is 12.5 Mbyte, LV7.1 is 17.2 Mbyte, and LV8 would like to be 80 Mbyte. Using the "stripped" down version of the RTE it is 25 Mbyte. If you are in Romania, downloading via a Dial-up line this is a serious problem. Even for slow broadband (256K) it takes a fair chunk of time. Does anyone have any suggestions as to how I can strip out the bits in the LV8 RTE that are not required to reduce the installer size? Thanks, Bart

Thanks Loius, I'll give it a try! Bart Schroder

Hello, does anyone know how to make a trace on a Labview Graph persistant. One way would be to find a way to avoid the deletion of the trace when the graph is redrawn. I have been able to do this witha bit map graph, but the management overhead is serious, and the graph is slower than a native graph. The idea here is to be able to show a visual history of previous plots - much like you can see on some scopes. Any help very welcome, Bart Schroder