How to use comdlg.dll in labview

[naveen_k]

I want to call OPENFILENAMEA function in comdlg

https://docs.microsoft.com/en-us/windows/win32/api/commdlg/ns-commdlg-openfilenamea
in this link you can find data structure of this function.

Anyone please suggest me to configure it in dll call. I tried with cluster and discrete values i can't do it.

Here i attached my code and dll.

[wiebe@CARYA · Accepted solution]

From 16 years ago:

How-to-open-multiple-files-in-LabVIEW 

It would need adjustments for LabVIEW 64 bit...

[naveen_k]

Thank you sir. It works in 32 bit.

I have no idea what need to change for 64 bit.

can you guide me ?, please

[rolfk]

You would have to go through all the VIs and make anything that contains a handle (hinst..., hwnd....,) or a pointer (lp....) to be pointer sized integers. That can't be done for numerics inside clusters so you would have to create two seperate clusters, one for 32-bit where these entities are 32-bit integers and one for 64-bit where these entitities are 64-bit.

[wiebe@CARYA]

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@naveen_k wrote:

Thank you sir. It works in 32 bit.

I have no idea what need to change for 64 bit.

can you guide me ?, please

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In short, change all 32 bit integers that are pointers to pointer sized integers.

There's not really a deterministic way to tell if handles are pointers or not. But allocated memory certainly is...

If you only use 32 bit LabVIEW, you won't need to implement the 64 bit version (until you switch of course).

[naveen_k]

I changed all 32 bit integers to I64 (signed 64 bit integer). and dll entries as Signed pointer sized interger.
Still it is not working in 64 bit.

Please help me to overcome this.

[rolfk]

First you should of course show what you have done when asking for help!! We do not have a crystal ball to see what your VI looks like on your computer.

Second, expecting this scream for help already I reworked the VI to work for both 32-bit and 64-bit and also cleaned it up considerably. Still needs some more testing but this is what it will look like.

[naveen_k]

Sorry Sir. Here I attached LLB which i modified

[rolfk · Accepted solution]

So I created the VI and did some prelimenary tests which seem to indicate that it works. This should work for both 32-bit and 64-bit LabVIEW. The attached ZIP file contains VIs that will work for LabVIEW 2009 and higher. Lower versions do not support 64-bit code options so this version can not be backsaved to an earlier version without significant modifications.

[naveen_k]

How to calculate IstructSize. It seems 7C (124 bytes). but it accepts 88 (136 bytes).

Can you explain this please?