CDC* PASCAL CDC::FromHandle(HDC hDC)
{
CHandleMap* pMap = afxMapHDC(TRUE); //create map if not exist
ASSERT(pMap != NULL);
CDC* pDC = (CDC*)pMap->FromHandle(hDC);
ASSERT(pDC == NULL || pDC->m_hDC == hDC);
return pDC;
}
void CDC::ReleaseOutputDC() // Release the Output DC
{
#ifdef _DEBUG
CHandleMap* pMap = afxMapHDC();
if (pMap != NULL && pMap->LookupPermanent(m_hDC) == this)
{
TRACE(traceAppMsg, 0, "Cannot Release Output hDC on Attached CDC.\n");
ASSERT(FALSE);
}
#endif
m_hDC = NULL;
}
void CDC::SetOutputDC(HDC hDC) // Set the Output DC
{
#ifdef _DEBUG
CHandleMap* pMap = afxMapHDC();
if (pMap != NULL && pMap->LookupPermanent(m_hDC) == this)
{
TRACE0("Cannot Set Output hDC on Attached CDC.\n");
ASSERT(FALSE);
}
#endif
m_hDC = hDC;
}
HDC CDC::Detach()
{
HDC hDC = m_hDC;
if (hDC != NULL)
{
CHandleMap* pMap = afxMapHDC(); // don't create if not exist
if (pMap != NULL)
pMap->RemoveHandle(m_hDC);
}
ReleaseAttribDC();
m_hDC = NULL;
return hDC;
}
BOOL CDC::Attach(HDC hDC)
{
ASSERT(m_hDC == NULL); // only attach once, detach on destroy
ASSERT(m_hAttribDC == NULL); // only attach to an empty DC
if (hDC == NULL)
return FALSE;
CHandleMap* pMap = afxMapHDC(TRUE); // create map if not exist
ASSERT(pMap != NULL);
pMap->SetPermanent(m_hDC = hDC, this);
SetAttribDC(m_hDC); // Default to same as output
return TRUE;
}
void PASCAL CDC::DeleteTempMap()
{
CHandleMap* pMap = afxMapHDC();
if (pMap != NULL)
pMap->DeleteTemp();
}
