怎么将mfc对话框右上角的关闭按钮还原？

BOOL CMainFrame::ChangeDlgStyle(int resInt)

{

	HINSTANCE hInst=AfxFindResourceHandle(MAKEINTRESOURCE(resInt),RT_DIALOG);

	HRSRC hRes=::FindResource(hInst,MAKEINTRESOURCE(resInt),RT_DIALOG);

	DWORD sz = ::SizeofResource(hInst, hRes);// 284

	HGLOBAL hTemplate=::LoadResource(hInst,hRes);

	DLGTEMPLATEEX *pTemplate=(DLGTEMPLATEEX *)LockResource(hTemplate);

	HWND hDlg=0;

	BYTE *pByte=new BYTE[sz];

//

	if(pTemplate->signature==0xFFFF)

	{//ex

		DLGTEMPLATEEX *pNewTmp=(DLGTEMPLATEEX *)lpdwAlign((LPDWORD)pByte);

		CopyMemory(pNewTmp,pTemplate,sz);

		pNewTmp->style &= ~WS_CAPTION;

		pNewTmp->style &= ~DS_MODALFRAME;

		pNewTmp->style &= ~WS_POPUP;

		pNewTmp->style &= ~WS_VISIBLE;

		pNewTmp->style |= WS_BORDER;

		pNewTmp->style |= WS_CHILD;

		hDlg= CreateDialogIndirect(hInst,     // handle to application instance

				(const DLGTEMPLATE *)pNewTmp, // pointer to dialog box template

								this->m_hWnd, // handle to owner window

								0);           // pointer to dialog box procedure

	}

	else

	{//

		DLGTEMPLATE *pNewTmp=(DLGTEMPLATE *)lpdwAlign((LPDWORD)pByte);

		CopyMemory(pNewTmp,pTemplate,sz);

		pNewTmp->style &= ~WS_CAPTION;

		pNewTmp->style &= ~DS_MODALFRAME;

		pNewTmp->style &= ~WS_POPUP;

		pNewTmp->style &= ~WS_VISIBLE;

		pNewTmp->style |= WS_BORDER;

		pNewTmp->style |= WS_CHILD;

		hDlg= CreateDialogIndirect(hInst,     // handle to application instance

				(const DLGTEMPLATE *)pNewTmp, // pointer to dialog box template

								this->m_hWnd, // handle to owner window

								0);           // pointer to dialog box procedure

	}

	UnlockResource(hTemplate);

	FreeResource(hTemplate);

	delete [] pByte;

//

	if(hDlg)

	{

		m_Dlg.SubclassWindow(hDlg);

		CRect rc;

		GetClientRect(&rc);

		CRect tbRc;

		m_wndToolBar.GetToolBarCtrl().GetWindowRect(&tbRc);// h=26

		CRect sbRc;

		m_wndStatusBar.GetStatusBarCtrl().GetWindowRect(&sbRc);// h=25

// view border 2

		m_Dlg.MoveWindow(0,tbRc.Height()-1,rc.Width(),rc.Height()-tbRc.Height()-sbRc.Height()+1,FALSE);

		m_Dlg.ShowWindow(SW_SHOW);

		return TRUE;

	}

	return FALSE;

}