DLL interfacing with mixed value and reference types

Question

I'm currently trying to work with a supplied DLL.
I have header files and all, and the DLL import wizard does a decent job of importing the DLL functions but there are some data types which simply can't be handled.
The DLL requires usage of a data type which is a struct with value and reference data types.  I could theoretically replace the references with simple U32s but much of the required information in the data is in the data structures referenced by the pointers.
How do I go about implementing this seeing how I need to be able to pass the data back into the DLL in its original form (value and reference types).
I have something like the following:
struct Item {
Int Device,
*Item Next
*Item Previous
*Data Datastruct
I have downloaded the WDK from Microsoft, have CVI and Visual Studio 2008 available.  I'm not very experienced at this end of things...   I can deal with Structs with pure value types but how do I get at the data in the reference types?
I strongly suspect I need a wrapper DLL, but how is the best way to go about this?
Shane.
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Answer 1

Hi Shane,
To be honest, I don't understand why you have to pass the ENTIRE structue (if it's "Item" structure. The pointer to the next and the previous item should be held and manituplated in the DLL, doesn't it?
Operate within classes....
Are you talking about Labview Classes? I didn't use it yet. Sorry.
Convert Linked List to Array You can't store all elements by value in a cluster, because it's kind of recursive. The next pointer leads to the same Item structure (with it's own next pointer. If it's a circulary-linked-list it will never stop)
Or did you mean to store the pointers as a U32 value? That should work.
Output the struct as a binary blob Yes, why not ! But that lets me assume you don't know the concrete "Datastructure" ?!
I'm honest again I can't see the important information you mentioned if you pass the Data structure as a binary blob.
Read-only is a very good idea. If you don't need to tweak the pointers in the list you should avoid it.
Balze