内存初始化问题

INT* pData2 = new INT[nPixelCount];
memset(pData2, 0, sizeof(INT)*nPixelCount);
memcpy(pData2, pData, sizeof(INT)*nPixelCount);

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WCHAR* z_pDriveStr = new WCHAR[z_szAllDriveStr + sizeof(_T(" "))];

if(NULL == z_pDriveStr)
{
goto _RESULT;
}

ZeroMemory(z_pDriveStr, z_szAllDriveStr + sizeof(_T(" ")));

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typedef struct _itemData
{
HTREEITEM hItem;
CString strPath;
CString ItemName;
CString UpTime;;
ULONGLONG Size;
DWORD CheckState;
_itemData()
{
hItem = NULL;
strPath = _T("");
ItemName = _T("");
UpTime = _T("");
Size = 0;
CheckState = DUICHECKBOX_UNCHECKED;
}
}*ITEM_DATAPTR,ITEM_DATA;