Problems passing arrays using COM

Hi everybody,
I have a COM interfcae, which use automation, having the next method:

[id(1), helpstring("method Register")HRESULT Register([in]int iLength, [in, size_is(iLength)] BSTR bstrarrPrms[]);

The problem is, that when from the client I try to pass the BSTR array, I can see in debug that only the first value of the received array (in the server) match the sent array values. The rest is
something haotic ("???"," ", etc).
I can use only the SAFEARRAY to pass arrays? In this mode doesn't work?
(I got the idea to use this way from the MIDL compiler reference, its more simpliest then using SAFEARRAYs).
Thanx, Tibi
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I would pass a structure in the form of

typedef struct _Data{
      long            Num;
      [size_is(NumNum)]BSTR* pList;
} Data,*pData;

to the function:

func([in] pData DataPtr);

you just have to create the struct in the sender.

Can you post the client side code that is passing the array?

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well :

//lets say we have

const some_number = 100;

BSTR *dat;
dat = new BSTR[ some_number ];

Data dat_struct;
dat_struct.Num = some_number;
dat_struct.pList = dat;

func( &dat_struct );

//that's it

// cleanup:
delete[] dat;
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tmolnarAuthor Commented:
I tried in two ways: dynamic allocation using "calloc" or static mode using an
array declaration (to see how its work).

typedef struct {
    char *name;
    char *val;
} entry;


BSTR* pbstrarrPrms = (BSTR*)calloc(NR_ENTRIES, sizeof(BSTR));
BSTR  bstrarrPrms [NR_ENTRIES];

for(int i=0; i<NR_ENTRIES+2;i++)
    pbstrarrPrms[i] = entries[i].val;
    bstrarrPrms[i]  = entries[i].val;
hr = pIRegister->Register(NR_ENTRIES,   bstrarrPrms);
hr = pIRegister->Register(NR_ENTRIES,   pstrarrPrms);

  In both cases I have the same result. The first value is OK, the nexts are not.
  If I replace 'entries[i].val' with a normal string like "everything"-->
    pbstrarrPrms[i] = "trying";
    bstrarrPrms[i]  = "to pass";
--> the result is the same.

tmolnarAuthor Commented:
I tried what yoy told me, but I got
HRESULT error code
 hr = Error: missing opetator, and the code is not reached at the server side.
(I used your code..)
tmolnarAuthor Commented:
Using the SAFEARRAY structure incorporated in a VARIANT structure I can send arrays. Why don't work using normal MIDL features?
tmolnarAuthor Commented:
Using the SAFEARRAY structure incorporated in a VARIANT structure I can send arrays. Why don't work using normal MIDL features?
(Becouse I have dual interface, and I have marshaller only to VARIANT tags, offered from oleaut32.dll ???)
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