SafeArrayAccessData function (oleauto.h)

Article
02/22/2024

Increments the lock count of an array, and retrieves a pointer to the array data.

Syntax

HRESULT SafeArrayAccessData(
  [in]  SAFEARRAY  *psa,
  [out] void HUGEP **ppvData
);

Parameters

[in] psa

An array descriptor created by SafeArrayCreate.

[out] ppvData

The array data.

Return value

This function can return one of these values.

Return code	Description
S_OK	Success.
E_INVALIDARG	The argument psa is not valid.
E_UNEXPECTED	The array could not be locked.

Remarks

After calling SafeArrayAccessData, you must call the SafeArrayUnaccessData function to unlock the array.

Examples

The following example sorts a safe array of one dimension that contains BSTRs by accessing the array elements directly. This approach is faster than using SafeArrayGetElement and SafeArrayPutElement.

long i, j, min; 
BSTR bstrTemp;
BSTR HUGEP *pbstr;
HRESULT hr;

// Get a pointer to the elements of the array.
hr = SafeArrayAccessData(psa, (void HUGEP**)&pbstr);
if (FAILED(hr))
goto error;

// Selection sort.
for (i = 0; i < psa->rgsabound.cElements-1; i++)
{
   min = i;
   for (j = i+1; j < psa->rgsabound.cElements; j++)
   {
      if (wcscmp(pbstr[j], pbstr[min]) < 0)
         min = j; 
   }

   // Swap array[min] and array[i].
   bstrTemp = pbstr[min];
   pbstr[min] = pbstr[i];
   pbstr[i] = bstrTemp;

}

SafeArrayUnaccessData(psa);

Requirements

Requirement	Value
Target Platform	Windows
Header	oleauto.h
Library	OleAut32.lib
DLL	OleAut32.dll

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