CFileDialog的钩子函数解决对话框的多选之DoModal问题

// 钩子函数
UINT_PTR CALLBACK MyOFNHookProc( HWND hdlg, // handle to child dialog box
UINT uiMsg, // message identifier
WPARAM wParam, // message parameter
LPARAM lParam // message parameter
)
{
int nResult = FALSE;
if (hdlg == NULL)
return 0;
#ifdef _DEBUG
// from "_AfxCommDlgProc()" of the file "dlgcomm.cpp"
_AFX_THREAD_STATE* pThreadState = AfxGetThreadState();
if (pThreadState->m_pAlternateWndInit != NULL)
pThreadState->m_pAlternateWndInit = NULL;
#endif
switch(uiMsg)
{
case WM_NOTIFY:
{
LPOFNOTIFY pOfn = (LPOFNOTIFY)lParam;
switch(pOfn->hdr.code)
{
case CDN_SELCHANGE:
{
TCHAR dummy_buffer;
// Get the required size for the 'files' buffer
HWND hOwner = GetParent(hdlg);
HWND hParent = GetParent(hOwner);
UINT nfiles = CommDlg_OpenSave_GetSpec(hOwner, &dummy_buffer, 1);
// Get the required size for the 'folder' buffer
int cbLength = CommDlg_OpenSave_GetSpec(GetParent(hdlg), NULL, 0);
cbLength += _MAX_PATH;
if(cbLength>(pOfn->lpOFN)->nMaxFile)
{
delete (pOfn->lpOFN)->lpstrFile;
(pOfn->lpOFN)->lpstrFile = new TCHAR[cbLength];
ZeroMemory((pOfn->lpOFN)->lpstrFile,cbLength);
(pOfn->lpOFN)->nMaxFile = cbLength;
}
nResult = TRUE;
break;
}
default:
break;
}
break;
}
default:
break;
}
return nResult;
}
#define NAMEBUF 1024
// 调用函数
void CMultiSelectDlg::OnButton1()
{
m_listbox.ResetContent();
m_static.SetWindowText(_T("0 files selected"));
TCHAR szFilters[]= _T("MyType Files (*.doc)|*.doc||");
// Create an Open dialog; the default file name extension is ".doc".
CFileDialog fileDlg(TRUE, _T("doc"), _T("*.doc"),
OFN_FILEMUSTEXIST | OFN_HIDEREADONLY|OFN_ALLOWMULTISELECT, szFilters);
fileDlg.m_ofn.lpstrFile=new TCHAR[NAMEBUF]; // 重新定义lpstrFile 缓冲大小
memset(fileDlg.m_ofn.lpstrFile,0,NAMEBUF); // 初始化定义的缓冲
fileDlg.m_ofn.nMaxFile = NAMEBUF; // 重定义nMaxFile
fileDlg.m_ofn.lpfnHook = (LPOFNHOOKPROC)MyOFNHookProc;
INT_PTR ret = fileDlg.DoModal();
if (ret == IDOK)
{
int width = 0;
CString str;
CDC *pDC = m_listbox.GetDC();
int saved = pDC->SaveDC();
pDC->SelectObject(GetFont());
UINT count = 0;
POSITION pos = fileDlg.GetStartPosition();
while (pos)
{
str = fileDlg.GetNextPathName(pos);
m_listbox.AddString(str);
CSize size(0, 0);
size = pDC->GetTextExtent(str);
width = width > size.cx ? width : size.cx;
++count;
}
pDC->RestoreDC(saved);
ReleaseDC(pDC);
m_listbox.SetHorizontalExtent(width + 5);
str.Format(_T("%u files selected"), count);
m_static.SetWindowText(str);
}
DWORD dwCode = CommDlgExtendedError();
if (FNERR_BUFFERTOOSMALL==dwCode)
{
AfxMessageBox(_T("获取文件路径失败！"));
}
delete []fileDlg.m_ofn.lpstrFile;
fileDlg.m_ofn.lpstrFile = NULL;
}