猜数字游戏，当填入大于999的数字时，弹出对话框，这个程序代码我怎么也找不到在哪里写的。。。

1. // guess_numberDlg.cpp : implementation file
   //
   
   #include "stdafx.h"
   #include "guess_number.h"
   #include "guess_numberDlg.h"
   
   #ifdef _DEBUG
   #define new DEBUG_NEW
   #undef THIS_FILE
   static char THIS_FILE[] = __FILE__;
   #endif
   
   /////////////////////////////////////////////////////////////////////////////
   // CAboutDlg dialog used for App About
   
   class CAboutDlg : public CDialog
   {
   public:
   	CAboutDlg();
   
   // Dialog Data
   	//{{AFX_DATA(CAboutDlg)
   	enum { IDD = IDD_ABOUTBOX };
   	//}}AFX_DATA
   
   	// ClassWizard generated virtual function overrides
   	//{{AFX_VIRTUAL(CAboutDlg)
   	protected:
   	virtual void DoDataExchange(CDataExchange* pDX);    // DDX/DDV support
   	//}}AFX_VIRTUAL
   
   // Implementation
   protected:
   	//{{AFX_MSG(CAboutDlg)
   	//}}AFX_MSG
   	DECLARE_MESSAGE_MAP()
   };
   
   CAboutDlg::CAboutDlg() : CDialog(CAboutDlg::IDD)
   {
   	//{{AFX_DATA_INIT(CAboutDlg)
   	//}}AFX_DATA_INIT
   }
   
   void CAboutDlg::DoDataExchange(CDataExchange* pDX)
   {
   	CDialog::DoDataExchange(pDX);
   	//{{AFX_DATA_MAP(CAboutDlg)
   	//}}AFX_DATA_MAP
   }
   
   BEGIN_MESSAGE_MAP(CAboutDlg, CDialog)
   	//{{AFX_MSG_MAP(CAboutDlg)
   		// No message handlers
   	//}}AFX_MSG_MAP
   END_MESSAGE_MAP()
   
   /////////////////////////////////////////////////////////////////////////////
   // CGuess_numberDlg dialog
   
   CGuess_numberDlg::CGuess_numberDlg(CWnd* pParent /*=NULL*/)
   	: CDialog(CGuess_numberDlg::IDD, pParent)
   {
   	//{{AFX_DATA_INIT(CGuess_numberDlg)
   	m_list = _T("");
   	m_num = 0;
   	//}}AFX_DATA_INIT
   	// Note that LoadIcon does not require a subsequent DestroyIcon in Win32
   	m_hIcon = AfxGetApp()->LoadIcon(IDR_MAINFRAME);
   }
   
   void CGuess_numberDlg::DoDataExchange(CDataExchange* pDX)
   {
   	CDialog::DoDataExchange(pDX);
   	//{{AFX_DATA_MAP(CGuess_numberDlg)
   	DDX_Control(pDX, ID_Start, m_start);
   	DDX_Text(pDX, IDC_List, m_list);
   	DDX_Text(pDX, IDC_InputNum, m_num);
   	DDV_MinMaxInt(pDX, m_num, 0, 999);
   	//}}AFX_DATA_MAP
   }
   
   BEGIN_MESSAGE_MAP(CGuess_numberDlg, CDialog)
   	//{{AFX_MSG_MAP(CGuess_numberDlg)
   	ON_WM_SYSCOMMAND()
   	ON_WM_PAINT()
   	ON_WM_QUERYDRAGICON()
   	ON_BN_CLICKED(IDC_Guess, OnGuess)
   	ON_BN_CLICKED(IDC_See, OnSee)
   	ON_BN_CLICKED(ID_Start, OnStart)
   	//}}AFX_MSG_MAP
   END_MESSAGE_MAP()
   
   /////////////////////////////////////////////////////////////////////////////
   // CGuess_numberDlg message handlers
   
   BOOL CGuess_numberDlg::OnInitDialog()
   {
   	CDialog::OnInitDialog();
   
   	// Add "About..." menu item to system menu.
   
   	// IDM_ABOUTBOX must be in the system command range.
   	ASSERT((IDM_ABOUTBOX & 0xFFF0) == IDM_ABOUTBOX);
   	ASSERT(IDM_ABOUTBOX < 0xF000);
   
   	CMenu* pSysMenu = GetSystemMenu(FALSE);
   	if (pSysMenu != NULL)
   	{
   		CString strAboutMenu;
   		strAboutMenu.LoadString(IDS_ABOUTBOX);
   		if (!strAboutMenu.IsEmpty())
   		{
   			pSysMenu->AppendMenu(MF_SEPARATOR);
   			pSysMenu->AppendMenu(MF_STRING, IDM_ABOUTBOX, strAboutMenu);
   		}
   	}
   
   	// Set the icon for this dialog.  The framework does this automatically
   	//  when the application's main window is not a dialog
   	SetIcon(m_hIcon, TRUE);			// Set big icon
   	SetIcon(m_hIcon, FALSE);		// Set small icon
   	
   	// TODO: Add extra initialization here
   	
   	return TRUE;  // return TRUE  unless you set the focus to a control
   }
   
   void CGuess_numberDlg::OnSysCommand(UINT nID, LPARAM lParam)
   {
   	if ((nID & 0xFFF0) == IDM_ABOUTBOX)
   	{
   		CAboutDlg dlgAbout;
   		dlgAbout.DoModal();
   	}
   	else
   	{
   		CDialog::OnSysCommand(nID, lParam);
   	}
   }
   
   // If you add a minimize button to your dialog, you will need the code below
   //  to draw the icon.  For MFC applications using the document/view model,
   //  this is automatically done for you by the framework.
   
   void CGuess_numberDlg::OnPaint() 
   {
   	if (IsIconic())
   	{
   		CPaintDC dc(this); // device context for painting
   
   		SendMessage(WM_ICONERASEBKGND, (WPARAM) dc.GetSafeHdc(), 0);
   
   		// Center icon in client rectangle
   		int cxIcon = GetSystemMetrics(SM_CXICON);
   		int cyIcon = GetSystemMetrics(SM_CYICON);
   		CRect rect;
   		GetClientRect(&rect);
   		int x = (rect.Width() - cxIcon + 1) / 2;
   		int y = (rect.Height() - cyIcon + 1) / 2;
   
   		// Draw the icon
   		dc.DrawIcon(x, y, m_hIcon);
   	}
   	else
   	{
   		CDialog::OnPaint();
   	}
   }
   
   // The system calls this to obtain the cursor to display while the user drags
   //  the minimized window.
   HCURSOR CGuess_numberDlg::OnQueryDragIcon()
   {
   	return (HCURSOR) m_hIcon;
   }
   
   
   void CGuess_numberDlg::OnGuess() 
   {
   	// TODO: Add your control notification handler code here
   	UpdateData(true);
   	CString str;
   	if(m_num>rnd)
   		str="太大了";
   	else if(m_num<rnd)
   		str="太小了";
   	else 
   		{str="恭喜猜中";
   			m_start.EnableWindow(true);}
   	m_list=m_list+str+"\r\n";
       UpdateData(false); 
   }
   
   void CGuess_numberDlg::OnSee() 
   {
   	// TODO: Add your control notification handler code here
      CString str;
      str.Format("随机数：%d",rnd);
      MessageBox(str);
   }
   
   
   void CGuess_numberDlg::OnStart() 
   {
   	// TODO: Add your control notification handler code here
      srand(time(NULL));
      rnd=rand()%1000;
      m_start.EnableWindow(false);
      m_list="";
      m_num=0;
      UpdateData(false);
   }
   

   

    

183行UpdateData(true); 会触发73行DoDataExchange函数，在DoDataExchange中DDV_MinMaxInt(pDX, m_num, 0, 999);验证数据有效性时会弹出提示框。   如果你不想要这个提示框，可以不使用DDV_MinMaxInt，而是写自己的验证逻辑。