自定义MFC打开保存对话框的扩展名

1、这里的顶目名称是D-TriNet，文档扩展名是.dtn和.csv。 要让打开/保存对话框支持多个扩展名，最简单的方法是修改资源文件中的IDR_DTriNetTYPE字段： STRINGTABLE BEGIN IDR_MAINFRAME "D-TriNet" IDR_DTriNetTYPE "nDTriNetnD-TriNetnD-TriNet Files(*.dtn;*.csvn.dtn;.csvnDTriNet.DocumentnD-TriNet.Document" END 这样做的不足是，文件虽然可以有多个扩展名，但仍然只分为两类："D-T

2、riNet Files"和"All Files"。要想更细致地分类，需要重写相关的虚函数，具体做法不唯一，我觉得比较好的一种是重写CDocManager:DoPromptFileName。 下面的文字有些凌乱，因为它的内容是按照我的探索过程组织的。 首先考虑打开对话框。第一步是要弄清，打开对话框是什么时候（在哪）弹出来的？ 默认情况下，CDTriNetApp调用CWinApp:OnFileOpen方法处理FileOpen事件： ON_COMMAND(ID_FILE_OPEN, &CWinApp:OnFileOpen CWinApp:OnFileOpen又调

3、用CDocManager:OnFileOpen处理FileOpen事件： void CWinApp:OnFileOpen( ENSURE(m_pDocManager != NULL; m_pDocManager->OnFileOpen(; CDocManager:OnFileOpen显示对话框与用户交互，然后调用CWinApp:OpenDocumentFile方法： void CDocManager:OnFileOpen( / prompt the user (with all document templates CString newName; if (!DoPromptFileNa

4、me(newName, AFX_IDS_OPENFILE, OFN_HIDEREADONLY | OFN_FILEMUSTEXIST, TRUE, NULL return; / open cancelled AfxGetApp(->OpenDocumentFile(newName; / if returns NULL, the user has already been alerted 显然，一种可能的解决办法是绕过CWinApp和CDocManager，在CDTriNetApp:OnFileOpen方法中显示自定义对话框，然后调用CWinApp:OpenDocumentFile方法。

5、ON_COMMAND(ID_FILE_OPEN, &CDTriNetApp:OnFileOpen void CDTriNetApp:OnFileOpen( LPCTSTR szFilter = L"DTriNet文件(*.dtn|*.dtn|CSV文件(*.csv|*.csv|所有文件(*.*|*.*|" CFileDialog oFileDlg(TRUE, L".dtn", NULL, 4|2, szFilter; if(oFileDlg.DoModal( = IDOK OpenDocumentFile(oFileDlg.GetFileName

6、(; / CDTriNetApp不需要重写CWinApp:OpenDocumentFile方法 现在考虑保存对话框。第一步仍然是弄清，保存对话框是什么时候（在哪）弹出来的？ 分发消息时，调用了CDocument:DoFileSave虚方法： BOOL CDocument:DoFileSave( DWORD dwAttrib = GetFileAttributes(m_strPathName; if (dwAttrib & FILE_ATTRIBUTE_READONLY / we do not have read-write access or the file does not (no

7、w exist if (!DoSave(NULL TRACE(traceAppMsg, 0, "Warning: File save with new name failed.n" return FALSE; else if (!DoSave(m_strPathName TRACE(traceAppMsg, 0, "Warning: File save failed.n" return FALSE; return TRUE; CDocument:DoFileSave调用CDocument:DoSave，也是一个虚方法：（注：没有DoSaveAs方法，lp

8、szPathName参数决定了CDocumen t:DoSave是表现为“保存”还是“另存为”。） BOOL CDocument:DoSave(LPCTSTR lpszPathName, BOOL bReplace / Save the document data to a file / lpszPathName = path name where to save document file / if lpszPathName is NULL then the user will be prompted (SaveAs / note: lpszPathName can be different

9、 than 'm_strPathName' / if 'bReplace' is TRUE will change file name if successful (SaveAs / if 'bReplace' is FALSE will not change path name (SaveCopyAs CString newName = lpszPathName; if (newName.IsEmpty( CDocTemplate* pTemplate = GetDocTemplate(; ASSERT(pTemplate != NULL; n

10、ewName = m_strPathName; if (bReplace && newName.IsEmpty( newName = m_strTitle; / check for dubious filename int iBad = newName.FindOneOf(_T(":/" if (iBad != -1 newName.ReleaseBuffer(iBad; / append the default suffix if there is one CString strExt; if (pTemplate->GetDocString(str

11、Ext, CDocTemplate:filterExt && !strExt.IsEmpty( ASSERT(strExt0 = '.' int iStart = 0; newName += strExt.Tokenize(_T("", iStart; if (!AfxGetApp(->DoPromptFileName(newName, bReplace ? AFX_IDS_SAVEFILE : AFX_IDS_SAVEFILECOPY, OFN_HIDEREADONLY | OFN_PATHMUSTEXIST, FALSE, pTem

12、plate return FALSE; / don't even attempt to save CWaitCursor wait; if (!OnSaveDocument(newName if (lpszPathName = NULL / be sure to delete the file TRY CFile:Remove(newName; CATCH_ALL(e TRACE(traceAppMsg, 0, "Warning: failed to delete file after failed SaveAs.n" DELETE_EXCEPTION(e; END

13、_CATCH_ALL return FALSE; / reset the title and change the document name if (bReplace SetPathName(newName; return TRUE; / success CDocument:DoSave虚方法调用CWinApp:DoPromptFileName方法弹出保存对话框，后者又调用CDocManager:DoPromptFileName虚方法（情形与打开文件时相同）： BOOL CDocManager:DoPromptFileName(CString& fileName, UINT nIDS

14、Title, DWORD lFlags, BOOL bOpenFileDialog, CDocTemplate* pTemplate CFileDialog dlgFile(bOpenFileDialog, NULL, NULL, OFN_HIDEREADONLY | OFN_OVERWRITEPROMPT, NULL, NULL, 0; CString title; VERIFY(title.LoadString(nIDSTitle; dlgFile.m_ofn.Flags |= lFlags; CString strFilter; CString strDefault; if (pTemp

15、late != NULL ASSERT_VALID(pTemplate; _AfxAppendFilterSuffix(strFilter, dlgFile.m_ofn, pTemplate, &strDefault; else / do for all doc template POSITION pos = m_templateList.GetHeadPosition(; BOOL bFirst = TRUE; while (pos != NULL pTemplate = (CDocTemplate*m_templateList.GetNext(pos; _AfxAppendFilt

16、erSuffix(strFilter, dlgFile.m_ofn, pTemplate, bFirst ? &strDefault : NULL; bFirst = FALSE; / append the "*.*" all files filter CString allFilter; VERIFY(allFilter.LoadString (AFX_IDS_ALLFILTER; strFilter += allFilter; strFilter += (TCHAR'0' / next string please strFilter += _T(

17、"*.*" strFilter += (TCHAR'0' / last string dlgFile.m_ofn.nMaxCustFilter+; dlgFile.m_ofn.lpstrFilter = strFilter; dlgFile.m_ofn.lpstrTitle = title; dlgFile.m_ofn.lpstrFile = fileName.GetBuffer(_MAX_PATH; INT_PTR nResult = dlgFile.DoModal(; fileName.ReleaseBuffer(; return nResult = I

18、DOK; 看起来，重写CDocManager:DoPromptFileName方法比重写CDocument:DoSave方法要省事些： BOOL CDTriNetDocMgr:DoPromptFileName(CString& fileName, UINT nIDSTitle, DWORD lFlags, BOOL bOpenFileDialog, CDocTemplate* pTemplate LPCTSTR strFilter = L"DTriNet文件(*.dtn|*.dtn|CSV文件(*.csv|*.csv|所有文件(*.*|*.*|" CFileDialog dlgFile(bOpenFileDialog, NULL, NULL, OFN_HIDEREADONLY | OFN_OVERWRITEPROMPT, strFilter, NULL, 0; CString title; VERIFY(title.LoadString(nIDSTitle; dlgFile.m_ofn.lpstrTitle = title; dlgFile.m_ofn.lpstrFile = fileName.GetBuffer(_MAX_PATH; INT_PTR nRe