C / C++ / MFC

<br />
void CDialogbox::OnPaint()<br />
{<br />
	CPaintDC dc(this); // device context for painting<br />
	CRect m_rect;<br />
	GetWindowRect(m_rect);<br />
	//...<br />
	m_myclass.Draw(dc,m_rect); // Draw the image to dialog box<br />
		<br />
}<br />

<br />
void CDialogbox::OnPaint()<br />
{<br />
	CPaintDC dc(this); // device context for painting<br />
	CDC m_memdc;<br />
	m_memdc.CreateCompatibleDC(&dc); //Create a memory DC<br />
	CRect m_rect;<br />
	GetWindowRect(m_rect);<br />
	//...<br />
	m_myclass.Draw(dc,m_memdc); // First draw to memory DC<br />
	dc.BitBlt(m_rect.left,m_rect.right,m_rect.Width(),m_rect.Height(),&m_memdc,0,0,SRCCOPY); // Second copy from memory DC to Paint DC<br />
}<br />

<br />
	ITTAPI *TObj;<br />
	HRESULT hr;<br />
    hr = CoCreateInstance(<br />
                          CLSID_TAPI,<br />
                          NULL,<br />
                          CLSCTX_INPROC_SERVER,<br />
                          IID_ITTAPI,<br />
                          (LPVOID *)&TObj<br />
                         );<br />
    if ( FAILED(hr) )<br />
    {<br />
		MessageBox("CoCreateInstance on TAPI failed");<br />
    }<br />