How to pass a NULL string into a .net method

[Tesla1977]

Hey everyone,

 I am trying to use this method, and it wants a NULL to query all.

What do I wire into workspaceName? Empty String ("") does not work, just a constant with no characters inside does not work. Creating a byte array with 0 and converting to string does not work. With "does not work" i mean i get an empty array of workspaces, just like when i enter a notexisting workspaceName. I do not get an exception.

The method is working when entering an existing "workspaceName" into the input.

Thx in advance

[Christoph_D · Accepted solution]

Hi,

you cannot send a NULL with LabVIEW directly. If you absolutely need that you would have to create a wrapper DLL, that sends the NULL and you call the wrapper DLL instead of the original .NET DLL.

Best regards,
Christoph

[Tesla1977]

OK, thanks for the answer. As this is an absolute standard .net method from Microsoft, can this be implemented into LV or does any internal data handling prevent that entirely?

[Tesla1977]

For future use or other users:

With System.String (in mscorlib) there is the static property "empty" which works perfectly.

[D_A_N_A_S]

If it is for database related, you can try with "DB Tools Null" function (Connectivity->Database->Advanced).

Thanks,

Sanad MM