How to pass an array of structure from VB to C DLL

I Have a VB User defined Type
Type Owner
  Ownerid as string * 10
  Ownername as string * 20
End Type
Dim Ownerstruct(10) as Owner

Now how will i pass a reference of this type to a C DLL
The C DLL will later write into this structure after which the VB APP will use it.
LVL 1
laaxAsked:
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mcriderCommented:
Check out these microsoft KB articles:

How to Pass User-Defined Structure Containing Strings to DLL
http://support.microsoft.com/support/kb/articles/Q107/7/50.asp?LNG=ENG&SA=MSDN 

HOWTO: Pass a Point Structure to the Windows API by Value
http://support.microsoft.com/support/kb/articles/q161/3/01.asp?LNG=ENG&SA=MSDN 
 

 

Cheers!
0

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laaxAuthor Commented:
Hi mcrider,
   Thanks for your response yaar.
Let me explain my requirement more clearly.  

  I have a C DLL.  That should be used
both by another C program(later will be converted to .dll) and VB program.  With the same interface(function) both
C & VB should communicate with the C-DLL.

 
C-Program

typedef struct
{
   char cOwnerID[11];
   char cOwnerNm[40];
}owner;

owner **ppOwnerList;

main ()
{
  .....
  ppOwnerList = (owner**) malloc ( sizeof(owner*) * nRecCount );
  for ( int i = 0; i < nRecCount; i++ )
  {
    ppOwnerList[i] = ( owner* ) malloc( sizeof(owenr) );
  }

  // Then I pass this to C -Dll function
  myFunc(ppOwnerList, nRecCount);
 ....
  .....

} // end of main()

myFunc() has to populate the array of structures I pass and it works fine.

I want to call the same myFunc() from VB.

 How do I pass an array of structure from VB and populate
its fields inside myFunc() and get the value in VB?

For Ex.

Type Owner
  Ownerid as string * 10
  Ownername as string * 20
End Type
Dim OwnerStruct(10) as Owner

   I want to pass OwnerStruct() array to
the same myFunc() and get it populated.

  Your previous answer tell how to pass argument by 'by value', but I want 'by Ref'.  
  Waiting for solution ...

Thanks
0
mcriderCommented:
Have you tried something like:

   Declare Sub myFunc Lib "myDll" (ByRef N As Owner)


Cheers!
0
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