HOWTO: Get the Current Document in an MDI Application

• The Microsoft Foundation Classes (MFC), included with:

      - Microsoft Visual C++ for Windows, versions 1.0, 1.5, 1.51 1.52
      - Microsoft Visual C++ 32-bit Edition, versions 1.0, 2.0, 2.1, 4.0
  

SUMMARY

To get a pointer to the currently active document from an MDI application, use the CMDIFrameWnd::MDIGetActive() function. MDIGetActive() returns a pointer to the active CMDIChildWnd. This CMDIChildWnd * enables you to get a valid pointer to the currently active document via GetActiveDocument().

See the online help and "Class Libraries Reference" for more information about these functions.

MORE INFORMATION

The sample below shows how to get a valid pointer to the currently active document anywhere within an MDI application.

Sample Code

   /* Compile options needed:
   */
   void Some_Function()
   {
     CMyDoc   *pActiveDoc;      // CMyDoc derived from CDocument
     CMyFrame *pActiveFrame;    // CMyFrame derived from CMDIChildWnd
   
     pActiveFrame =(CMyFrame*)
               ((CMainFrame*)(AfxGetApp()->m_pMainWnd))->MDIGetActive();
    // MFC 2.5 and later versions contain AfxGetMainWnd(), which
    // can be used to gain access to the main window instead of
    // "AfxGetApp()->m_pMainWnd
   
     pActiveDoc = (CMyDoc*)pActiveFrame->GetActiveDocument();
   }