WM_KEYDOWN

1. 主要功能：

按下方向键、回车键、空格键时，处理不同的消息；

2. 主要技术：

2.1 WM_KEYDOWN;

2.2 

  GetCursorPos(&pt);
  ScreenToClient(hWnd, &pt);
....

  ClientToScreen(hWnd, &pt);
  SetCursorPos(pt.x, pt.y);

 

3. 源码：

// ChangableWin.cpp : Defines the entry point for the application.
//

#include "stdafx.h"
#include "resource.h"
#include <windows.h>
#include <math.h>

#define MAX_LOADSTRING 100

// Global Variables:
HINSTANCE hInst;        // current instance
TCHAR szTitle[MAX_LOADSTRING];        // The title bar text
TCHAR szWindowClass[MAX_LOADSTRING];        // The title bar text

// Foward declarations of functions included in this code module:
ATOM    MyRegisterClass(HINSTANCE hInstance);
BOOL    InitInstance(HINSTANCE, int);
LRESULT CALLBACK WndProc(HWND, UINT, WPARAM, LPARAM);
LRESULT CALLBACK About(HWND, UINT, WPARAM, LPARAM);

int APIENTRY WinMain(HINSTANCE hInstance,
                     HINSTANCE hPrevInstance,
                     LPSTR     lpCmdLine,
                     int       nCmdShow)
{
  // TODO: Place code here.
 MSG msg;
 HACCEL hAccelTable;

 // Initialize global strings
 LoadString(hInstance, IDS_APP_TITLE, szTitle, MAX_LOADSTRING);
 LoadString(hInstance, IDC_CHANGABLEWIN, szWindowClass, MAX_LOADSTRING);
 MyRegisterClass(hInstance);

 // Perform application initialization:
 if (!InitInstance (hInstance, nCmdShow))
 {
  return FALSE;
 }

 hAccelTable = LoadAccelerators(hInstance, (LPCTSTR)IDC_CHANGABLEWIN);

 // Main message loop:
 while (GetMessage(&msg, NULL, 0, 0))
 {
  if (!TranslateAccelerator(msg.hwnd, hAccelTable, &msg))
  {
   TranslateMessage(&msg);
   DispatchMessage(&msg);
  }
 }

 return msg.wParam;
}

 

//
//  FUNCTION: MyRegisterClass()
//
//  PURPOSE: Registers the window class.
//
//  COMMENTS:
//
//    This function and its usage is only necessary if you want this code
//    to be compatible with Win32 systems prior to the 'RegisterClassEx'
//    function that was added to Windows 95. It is important to call this function
//    so that the application will get 'well formed' small icons associated
//    with it.
//
ATOM MyRegisterClass(HINSTANCE hInstance)
{
 WNDCLASSEX wcex;

 wcex.cbSize = sizeof(WNDCLASSEX);

 wcex.style   = CS_HREDRAW | CS_VREDRAW;
 wcex.lpfnWndProc = (WNDPROC)WndProc;
 wcex.cbClsExtra  = 0;
 wcex.cbWndExtra  = 0;
 wcex.hInstance  = hInstance;
 wcex.hIcon   = LoadIcon(hInstance, (LPCTSTR)IDI_CHANGABLEWIN);
 wcex.hCursor  = LoadCursor(NULL, IDC_ARROW);
 wcex.hbrBackground = (HBRUSH)(COLOR_WINDOW+1);
 wcex.lpszMenuName = (LPCSTR)IDC_CHANGABLEWIN;
 wcex.lpszClassName = szWindowClass;
 wcex.hIconSm  = LoadIcon(wcex.hInstance, (LPCTSTR)IDI_SMALL);

 return RegisterClassEx(&wcex);
}

//
//   FUNCTION: InitInstance(HANDLE, int)
//
//   PURPOSE: Saves instance handle and creates main window
//
//   COMMENTS:
//
//        In this function, we save the instance handle in a global variable and
//        create and display the main program window.
//
BOOL InitInstance(HINSTANCE hInstance, int nCmdShow)
{
   HWND hWnd;

   hInst = hInstance; // Store instance handle in our global variable

   hWnd = CreateWindow(szWindowClass, szTitle, WS_OVERLAPPEDWINDOW,
      CW_USEDEFAULT, 0, CW_USEDEFAULT, 0, NULL, NULL, hInstance, NULL);

   if (!hWnd)
   {
      return FALSE;
   }

   ShowWindow(hWnd, nCmdShow);
   UpdateWindow(hWnd);

   return TRUE;
}

//
//  FUNCTION: WndProc(HWND, unsigned, WORD, LONG)
//
//  PURPOSE:  Processes messages for the main window.
//
//  WM_COMMAND - process the application menu
//  WM_PAINT - Paint the main window
//  WM_DESTROY - post a quit message and return
//
//
LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)
{
 int wmId, wmEvent;
 PAINTSTRUCT ps;
 HDC hdc;
 TCHAR szHello[MAX_LOADSTRING];

 static short xLength, yLength;
 enum picture {nothing=0, cross, circle};
 static enum picture iFlags[10][10];
 const int nums = 10;
 short x, y;
 RECT square;
 POINT pt;

 LoadString(hInst, IDS_HELLO, szHello, MAX_LOADSTRING);

 switch (message)
 {
 case WM_CREATE:
  for (x=0; x<10; x++)
  {
   for (y=0; y<10; y++)
   {
   if( (x+y)%3 ==1 )
   {
    
     iFlags[x][y] = cross;
   }
   else if ( (x+y)%3 ==2 )
   {
     iFlags[x][y] = circle;
   }
   else
   {
    iFlags[x][y] = nothing;

   }

   }

  }
  break;
 case WM_KEYDOWN:
  GetCursorPos(&pt);
  ScreenToClient(hWnd, &pt);
  x = pt.x/xLength;
  y = pt.y/yLength;
  
  switch(wParam)
  {
  case VK_LEFT:
   if (x>0)
   {
    x--;
   }
   else
   {
    MessageBeep(0);
   }
   break;
  case VK_UP:
   if (y>0)
   {
    y--;
   }
   else
   {
    MessageBeep(0);
   }
   break;
  case VK_RIGHT:
   if (x<nums)
   {
    x++;
   }
   else
   {
    MessageBeep(0);
   }
   break;
  case VK_DOWN:
   if (y<nums)
   {
    y++;
   }
   else
   {
    MessageBeep(0);
   }
   break;
  case VK_RETURN:
   SendMessage( hWnd, WM_LBUTTONDOWN, MK_LBUTTON, MAKELONG(x*xLength, y*yLength) );
   break;
  case VK_SPACE:
   SendMessage( hWnd, WM_RBUTTONDBLCLK, MK_RBUTTON, MAKELONG(x*xLength, y*yLength) );
   break;
  default:
   break;
  }

  pt.x = x*xLength + xLength/2;
  pt.y = y*yLength + yLength/2;
  ClientToScreen(hWnd, &pt);
  SetCursorPos(pt.x, pt.y);

  break;

  case WM_SIZE:
   xLength = LOWORD(lParam)/nums;
   yLength = HIWORD(lParam)/nums;
  break;

  case WM_LBUTTONDOWN:
   x = LOWORD(lParam)/xLength;
   y = HIWORD(lParam)/yLength;
   if (iFlags[x][y] == cross)
   {
    return 0;
   }
   if (iFlags[x][y] == nothing)
   {
    iFlags[x][y] == circle;
   }
   else if (iFlags[x][y] == circle)
   {
    iFlags[x][y] = nothing;
    square.left = x * xLength;
    square.top = y * yLength;
    square.right = (x+1) * xLength;
    square.bottom = (y+1) * yLength;
    InvalidateRect(hWnd, &square, FALSE);
   }
   
   break;
  case WM_RBUTTONDOWN:
   x = LOWORD(lParam)/xLength;
   y = HIWORD(lParam)/yLength;
   if (iFlags[x][y] == circle)
   {
    return 0;
   }
   if (iFlags[x][y] == nothing)
   {
    iFlags[x][y] = cross;
   }
   else if (iFlags[x][y] == cross)
   {
    iFlags[x][y] = nothing;
    square.left = x * xLength;
    square.top = y * yLength;
    square.right = (x+1) * xLength;
    square.bottom = (y+1) * yLength;
    InvalidateRect(hWnd, &square, FALSE);
   }
   break;
 
  case WM_COMMAND:
   wmId    = LOWORD(wParam);
   wmEvent = HIWORD(wParam);
   // Parse the menu selections:
   switch (wmId)
   {
    case IDM_ABOUT:
       DialogBox(hInst, (LPCTSTR)IDD_ABOUTBOX, hWnd, (DLGPROC)About);
       break;
    case IDM_EXIT:
       DestroyWindow(hWnd);
       break;
    default:
       return DefWindowProc(hWnd, message, wParam, lParam);
   }
   break;
  case WM_PAINT:
   hdc = BeginPaint(hWnd, &ps);
   // TODO: Add any drawing code here...
   RECT rt;
   GetClientRect(hWnd, &rt);
   DrawText(hdc, szHello, strlen(szHello), &rt, DT_CENTER);
   
   for (x=0; x<nums; x++)
   {
    for (y=0; y<nums; y++)
    {
     Rectangle(hdc, x*xLength, y*yLength, (x+1)*xLength, (y+1)*yLength);
     if (iFlags[x][y] == circle)
     {
      Ellipse(hdc, x*xLength, y*yLength, (x+1)*xLength, (y+1)*yLength);
     }
     else if (iFlags[x][y] == cross)
     {
      MoveToEx(hdc, x*xLength, y*yLength, (LPPOINT) NULL);
      LineTo(hdc, (x+1)*xLength, (y+1)*yLength);
      MoveToEx(hdc, x*xLength, (y+1)*yLength, (LPPOINT) NULL);
      LineTo(hdc, (x+1)*xLength, y*yLength);

     }
    }
   }
   
   
   EndPaint(hWnd, &ps);
   break;
  case WM_DESTROY:
   PostQuitMessage(0);
   break;
  default:
   return DefWindowProc(hWnd, message, wParam, lParam);
   }
   return 0;
}

// Mesage handler for about box.
LRESULT CALLBACK About(HWND hDlg, UINT message, WPARAM wParam, LPARAM lParam)
{
 switch (message)
 {
  case WM_INITDIALOG:
    return TRUE;

  case WM_COMMAND:
   if (LOWORD(wParam) == IDOK || LOWORD(wParam) == IDCANCEL)
   {
    EndDialog(hDlg, LOWORD(wParam));
    return TRUE;
   }
   break;
 }
    return FALSE;
}