helpstring in .NET

[DragonKing]

With Visual Studio 6++ we can use "helpstring" to implement online help in the COM object, which is to be used in LabView applications. A show context help window will pop up in LabView when an user places his cursor on the object.

Does LV support such online help feature for Microsoft .NET assembly??

Is there any work around??

Please advise.

Thanks!

-- DragonKing --

kingchiu@nortelnetworks.com

[Lycangeek]

I'm afraid that .NET did not carry that concept over from COM. There really isn't a system wide property for you to hook help into an object.

[thfwong2]

I was wondering how to get context help to work for my assembly object under Labview.  I still I don't know how to do it but I think there is something one can put in the assembly that has the same effect as helpsting in COM.  Need proof,  select the TestStand.Interop.API assembly(NationalInstruments.TestStand.Interop.API.dll) and chose the EngineClass interface.  Now create a invoke node and select the "DisplayLoginDialog" method and you will see that Context help is working properly even for .NET assembly object.

[Lycangeek]

I'm afraid I'm not seeing what you are seeing. I tried it with LV 8.0.1 and TestStand 31 and 3.5 but didn't see any specific help show up in the context window. Could you tell me what versions you were trying with? I've got so many released, beta and locally built versions of things on my computer, it's possible that it's interfering.

Also, while I don't know that this is the reason you might be seeing this, remember that Interop assemblies are just proxy .NET assemblies for regular COM objects, which do have the help support. It's possible that is what is feeding the context window.

[thfwong2]

I am currently using Labview 7.1.  I guess what I saw was that if a function have a return value then the context help in Labview would display a one line description right below the message "Invoke Method: functionName".  Now I looked at it a little close I realize it is not the same thing as helpstring in COM. 

However assembly does support different syntaxes to add descriptions to assembly object functions.  One way is to use System::ComponentModel::Description to describe a function .  For example in Managed C++ I can do this,

public __gc class foo: public IDisposable

{

public:

[Description(S"You can enter a description for the DoSomething function here...")]

Void DoSomething( );

};

A lot of tools would pick this up and display the description.  So here are my questions:

(1) Does Labview support any of the assembly help syntaxes?

(2) If answner to (1) is no, is there plan to add something in future releases of Labview to allow assembly developers to add context help for Labview developers?  (All the Labview developers using my assemblies are cursing me for not providing context help ;-<)

[Lycangeek]

I'm afraid the answer, as you have already discovered, is no - we don't provide such a feature.

Are we going to provide it? Well, I can say it sounds like a good idea. I'll need to look into it more to see what it would take to get it added. First guess is that it isn't going to make the new release (Europa) because the timeframe is too short. I'll try to post back when I learn more about it.