Step 9. Disconnect the Property Page

Override the CBasePropertyPage::OnDisconnect method to release any interfaces that you obtained in the OnConnect method. Also, if the user dismisses the property sheet without committing the changes, you should restore the original values if they have changed. There is no "OnCancel" method that gets called when the user cancels, so you need to keep track of whether the user has called OnApplyChanges. This example uses the m_lVal variable, described earlier:

HRESULT CGrayProp::OnDisconnect(void)
{
    if (m_pGray)
    {
        // If the user clicked OK, m_lVal holds the new value.
        // Otherwise, if the user clicked Cancel, m_lVal is the old value.
        m_pGray->SetSaturation(m_lVal);  
        m_pGray->Release();
        m_pGray = NULL;
    }
    return S_OK;
}