Manipulating the File Open/Save Filters

CDocTemplate *m_pTest1DocTemplate, m_pTest2DocTemplate

m_pTest1DocTemplate = new CMultiDocTemplate(IDR_TEST1TYPE, 
 RUNTIME_CLASS(CTest1Doc),
 RUNTIME_CLASS(CChildFrame), // custom MDI child frame
 RUNTIME_CLASS(CTest1View));

AddDocTemplate(m_pTest1DocTemplate);

m_pTest2DocTemplate = new CMultiDocTemplate(IDR_TEST2TYPE, 
 RUNTIME_CLASS(CTest2Doc),
 RUNTIME_CLASS(CChildFrame), // custom MDI child frame
 RUNTIME_CLASS(CTest2View));
AddDocTemplate(m_pTest2DocTemplate);

//Implementation of the base class virtual function
BOOL CCGPDocManager::DoPromptFileName(CString& fileName, UINT nIDSTitle, DWORD lFlags, BOOL bOpenFileDialog, CDocTemplate* pTemplate)
{
 CString cstrInitialDir = ""; 

 //Depending on the Template you can set the Initial Folder 
 if(pTemplate == g_theApp.m_pTest1DocTemplate)
 {
  cstrInitialDir = "c:\\Test\\Test1Files";
 }
 else if(pTemplate == g_theApp.m_pTest2DocTemplate)
 {
  cstrInitialDir = "c:\\Test\\Test2Files";
 }

 return CUtility::DoPromptFileName(cstrInitialDir, fileName, nIDSTitle, lFlags, bOpenFileDialog, pTemplate);
}

//m_pDocManager is already defined in the CWinApp class
m_pDocManager = new CCGPDocManager();

void CMainFrame::OnFileOpen() 
{
 CString cstrFileName;
	
 CDocTemplate *paDocTemplate[] = {g_theApp.m_pTest1DocTemplate, 
  g_theApp.m_pTest2DocTemplate, 
  NULL};

 if(!CUtility::DoPromptFileName("", cstrFileName, AFX_IDS_OPENFILE, 
  OFN_HIDEREADONLY | OFN_PATHMUSTEXIST, TRUE, 
  paDocTemplate))
   return;

 OpenDocumentFile(cstrFileName);
}

static BOOL DoPromptFileName(CString cstrInitialDir, CString& fileName, UINT nIDSTitle, DWORD lFlags, BOOL bOpenFileDialog, CDocTemplate **pTemplate);
static BOOL DoPromptFileName(CString cstrInitialDir, CString& fileName, UINT nIDSTitle, DWORD lFlags, BOOL bOpenFileDialog, CDocTemplate* pTemplate);
static void AppendFilterSuffix(CString& filter, OPENFILENAME& ofn, CDocTemplate* pTemplate, CString* pstrDefaultExt);

BOOL CUtility::DoPromptFileName(CString cstrInitialDir, CString& fileName, 
 UINT nIDSTitle, DWORD lFlags, 
 BOOL bOpenFileDialog, 
 CDocTemplate* pTemplate)
{
 CFileDialog dlgFile(bOpenFileDialog);

 CString title;
 VERIFY(title.LoadString(nIDSTitle));

 dlgFile.m_ofn.Flags |= lFlags;

 CString strFilter;
 CString strDefault;
 if(pTemplate != NULL)
 {
  ASSERT_VALID(pTemplate);
  AppendFilterSuffix(strFilter, dlgFile.m_ofn, pTemplate, &strDefault);
 }

 dlgFile.m_ofn.lpstrFilter = strFilter;
#ifndef _MAC
 dlgFile.m_ofn.lpstrTitle = title;
#else
 dlgFile.m_ofn.lpstrPrompt = title;
#endif
 dlgFile.m_ofn.lpstrFile = fileName.GetBuffer(_MAX_PATH);
	
 dlgFile.m_ofn.lpstrInitialDir = cstrInitialDir;

 BOOL bResult = dlgFile.DoModal() == IDOK ? TRUE : FALSE;
 fileName.ReleaseBuffer();
	
 CString strFilterExt;
 //Get the file extension of the template
 pTemplate->GetDocString(strFilterExt, CDocTemplate::filterExt);

 //Get the file extension of the selected file
 CString cstrSelFileExt = fileName.Right(fileName.GetLength() - fileName.ReverseFind('.'));

 cstrSelFileExt.MakeLower();
 strFilterExt.MakeLower();

 //compare both if not the same extension then return false
 if(strFilterExt.Find(cstrSelFileExt) == -1)
 {
  AfxMessageBox("Invalid extension", MB_OK | MB_ICONHAND);
  return FALSE;
 }
	
 return bResult;
}

BOOL CUtility::DoPromptFileName(CString cstrInitialDir, CString& fileName, 
 UINT nIDSTitle, DWORD lFlags, 
 BOOL bOpenFileDialog, 
 CDocTemplate **pTemplate)
{
 CFileDialog dlgFile(bOpenFileDialog);
 
 CString title;
 VERIFY(title.LoadString(nIDSTitle));

 dlgFile.m_ofn.Flags |= lFlags;

 CString strFilter;
 CString strDefault;
	
 int i = 0;

 while(pTemplate[i] != NULL)
 {
  ASSERT_VALID(pTemplate[i]);
  AppendFilterSuffix(strFilter, dlgFile.m_ofn, pTemplate[i], &strDefault);
  i++;
 }
 	
 dlgFile.m_ofn.lpstrFilter = strFilter;
#ifndef _MAC
 dlgFile.m_ofn.lpstrTitle = title;
#else
 dlgFile.m_ofn.lpstrPrompt = title;
#endif
 dlgFile.m_ofn.lpstrFile = fileName.GetBuffer(_MAX_PATH);
	
 dlgFile.m_ofn.lpstrInitialDir = cstrInitialDir;

 BOOL bResult = dlgFile.DoModal() == IDOK ? TRUE : FALSE;
 fileName.ReleaseBuffer();

 BOOL bExtMatched = FALSE;
 i = 0;
 while(pTemplate[i] != NULL)
 {
  CString strFilterExt;
  //Get the file extension of the template
  pTemplate[i]->GetDocString(strFilterExt, CDocTemplate::filterExt);

  //Get the file extension of the selected file
  CString cstrSelFileExt = fileName.Right(fileName.GetLength() - fileName.ReverseFind('.'));

  cstrSelFileExt.MakeLower();
  strFilterExt.MakeLower();

  if(strFilterExt.Find(cstrSelFileExt) != -1)
  {
   bExtMatched = TRUE;
   break;
  }

  i++;
 }

 if(!bExtMatched)
 {
  AfxMessageBox("Invalid extension", MB_OK | MB_ICONHAND);
  return FALSE;
 }
	
 return bResult;
}

void CUtility::AppendFilterSuffix(CString& filter, OPENFILENAME& ofn,
	CDocTemplate* pTemplate, CString* pstrDefaultExt)
{
 ASSERT_VALID(pTemplate);
 ASSERT_KINDOF(CDocTemplate, pTemplate);

 CString strFilterExt, strFilterName;
 if (pTemplate->GetDocString(strFilterExt, CDocTemplate::filterExt) &&
 ! strFilterExt.IsEmpty() &&
 pTemplate->GetDocString(strFilterName, CDocTemplate::filterName) &&
 ! strFilterName.IsEmpty())
 {
  // a file based document template - add to filter list
#ifndef _MAC
  ASSERT(strFilterExt[0] == '.');
#endif
  if (pstrDefaultExt != NULL)
  {
   // set the default extension
#ifndef _MAC
   *pstrDefaultExt = ((LPCTSTR)strFilterExt) + 1;  // skip the '.'
#else
   *pstrDefaultExt = strFilterExt;
#endif
   ofn.lpstrDefExt = (LPTSTR)(LPCTSTR)(*pstrDefaultExt);
   ofn.nFilterIndex = ofn.nMaxCustFilter + 1;  // 1 based number
  }

  // add to filter
  filter += strFilterName;
  ASSERT(!filter.IsEmpty());  // must have a file type name
  filter += (TCHAR)'\0';  // next string please
#ifndef _MAC
  filter += (TCHAR)'*';
#endif
  filter += strFilterExt;
  filter += (TCHAR)'\0';  // next string please
  ofn.nMaxCustFilter++;
 }
}