CComSafeArray Class
This class is a wrapper for the SAFEARRAY structure.
template < typename T, VARTYPE _vartype = _ATL_AutomationType< T >::type > class CComSafeArray
Parameters
- T
-
The type of data to be stored in the array.
CComSafeArray provides a wrapper for the SAFEARRAY Data Type class, making it a simple matter to create and manage single- and multidimensional arrays of almost any of the VARIANT-supported types.
CComSafeArray simplifies passing arrays between processes, and in addition provides extra security by checking array index values against upper and lower bounds.
The lower bound of a CComSafeArray can start at any user-defined value; however, arrays that are accessed through C++ should use a lower bound of 0. Other languages such as Visual Basic may use other bounding values (for example, -10 to 10).
Use CComSafeArray::Create to create a CComSafeArray object, and CComSafeArray::Destroy to delete it.
A CComSafeArray can contain the following subset of VARIANT data types:
| VARTYPE | Description |
|---|---|
| VT_I1 | char |
| VT_I2 | short |
| VT_I4 | int |
| VT_I4 | long |
| VT_I8 | longlong |
| VT_UI1 | byte |
| VT_UI2 | ushort |
| VT_UI4 | uint |
| VT_UI4 | ulong |
| VT_UI8 | ulonglong |
| VT_R4 | float |
| VT_R8 | double |
| VT_DECIMAL | decimal pointer |
| VT_VARIANT | variant pointer |
| VT_CY | Currency data type |
// Create a multidimensional array,
// then write and read elements
#include "stdafx.h"
#include "atlsafe.h"
int main(int argc, char* argv[])
{
// Define an array of character pointers
CComSafeArray<char> *pSar;
char cElement;
char cTable[2][3] = {'A','B','C','D','E','F'};
// Declare the variable used to store the
// array indexes
LONG aIndex[2];
// Define the array bound structure
CComSafeArrayBound bound[2];
bound[0].SetCount(3);
bound[0].SetLowerBound(0);
bound[1].SetCount(3);
bound[1].SetLowerBound(0);
// Create a new 2 dimensional array
// each dimension size is 3
pSar = new CComSafeArray<char>(bound,2);
// Use MultiDimSetAt to store characters in the array
for (int x = 0; x < 2; x++)
{
for (int y = 0; y < 3; y++)
{
aIndex[0] = x;
aIndex[1] = y;
HRESULT hr = pSar->MultiDimSetAt(aIndex,cTable[x][y]);
ATLASSERT(hr == S_OK);
}
}
// Use MultiDimGetAt to retrieve characters in the array
for (int x = 0; x < 2; x++)
{
for (int y = 0; y < 3; y++)
{
aIndex[0]=x;
aIndex[1]=y;
HRESULT hr = pSar->MultiDimGetAt(aIndex,cElement);
ATLASSERT(hr == S_OK);
ATLASSERT(cElement == cTable[x][y]);
}
}
return 0;
}
