首先新建一个Win32项目，注意，不是控制台项目。
新建一个源文件，将下面的代码复制进去，编译运行即可看见一个跳动的小球。
#include
#define ID_TIMER 1
LRESULT CALLBACK WndProc (HWND, UINT, WPARAM, LPARAM) ;
int WINAPI WinMain (HINSTANCE hInstance, HINSTANCE hPrevInstance,
PSTR szCmdLine, int iCmdShow) {
static TCHAR szAppName[] = TEXT ("Bounce") ;
HWND hwnd ;
MSG msg ;
WNDCLASS wndclass ;
wndclass.style = CS_HREDRAW | CS_VREDRAW ;
wndclass.lpfnWndProc = WndProc ;
wndclass.cbClsExtra = 0 ;
wndclass.cbWndExtra = 0 ;
wndclass.hInstance = hInstance ;
wndclass.hIcon = LoadIcon (NULL, IDI_APPLICATION) ;
wndclass.hCursor = LoadCursor (NULL, IDC_ARROW) ;
wndclass.hbrBackground = (HBRUSH) GetStockObject (WHITE_BRUSH) ;
wndclass.lpszMenuName = NULL ;
wndclass.lpszClassName = szAppName ;
if (!RegisterClass (&wndclass))
{
MessageBox ( NULL, TEXT ("This program requires Windows NT!"),
szAppName, MB_ICONERROR) ;
return 0 ;
}
hwnd = CreateWindow ( szAppName, TEXT ("Bouncing Ball"),
WS_OVERLAPPEDWINDOW,
CW_USEDEFAULT, CW_USEDEFAULT,
CW_USEDEFAULT, CW_USEDEFAULT,
NULL, NULL, hInstance, NULL) ;
ShowWindow (hwnd, iCmdShow) ;
UpdateWindow (hwnd) ;
while (GetMessage (&msg, NULL, 0, 0))
{
TranslateMessage (&msg) ;
DispatchMessage (&msg) ;
}
return msg.wParam ;
}
LRESULT CALLBACK WndProc (HWND hwnd, UINT iMsg, WPARAM wParam, LPARAM lParam)
{
static HBITMAP hBitmap ;
static int cxClient, cyClient, xCenter, yCenter, cxTotal, cyTotal,
cxRadius, cyRadius, cxMove, cyMove, xPixel, yPixel ;
HBRUSH hBrush ;
HDC hdc, hdcMem ;
int iScale ;
switch (iMsg)
{
case WM_CREATE:
hdc = GetDC (hwnd) ;
xPixel = GetDeviceCaps (hdc, ASPECTX) ;
yPixel = GetDeviceCaps (hdc, ASPECTY) ;
ReleaseDC (hwnd, hdc) ;
SetTimer (hwnd, ID_TIMER, 50, NULL) ;
return 0 ;
case WM_SIZE:
xCenter = (cxClient = LOWORD (lParam)) / 2 ;
yCenter = (cyClient = HIWORD (lParam)) / 2 ;
iScale = min (cxClient * xPixel, cyClient * yPixel) / 16 ;
cxRadius = iScale / xPixel ;
cyRadius = iScale / yPixel ;
cxMove = max (1, cxRadius / 2) ;
cyMove = max (1, cyRadius / 2) ;
cxTotal = 2 * (cxRadius + cxMove) ;
cyTotal = 2 * (cyRadius + cyMove) ;
if (hBitmap)
DeleteObject (hBitmap) ;
hdc = GetDC (hwnd) ;
hdcMem = CreateCompatibleDC (hdc) ;
hBitmap = CreateCompatibleBitmap (hdc, cxTotal, cyTotal) ;
ReleaseDC (hwnd, hdc) ;
SelectObject (hdcMem, hBitmap) ;
Rectangle (hdcMem, -1, -1, cxTotal + 1, cyTotal + 1) ;
hBrush = CreateHatchBrush (HS_DIAGCROSS, 0L) ;
SelectObject (hdcMem, hBrush) ;
SetBkColor (hdcMem, RGB (255, 0, 255)) ;
Ellipse (hdcMem, cxMove, cyMove, cxTotal - cxMove, cyTotal - cyMove) ;
DeleteDC (hdcMem) ;
DeleteObject (hBrush) ;
return 0 ;
case WM_TIMER:
if (!hBitmap)
break ;
hdc = GetDC (hwnd) ;
hdcMem = CreateCompatibleDC (hdc) ;
SelectObject (hdcMem, hBitmap) ;
BitBlt (hdc, xCenter - cxTotal / 2,
yCenter - cyTotal / 2, cxTotal, cyTotal,
hdcMem, 0, 0, SRCCOPY) ;
ReleaseDC (hwnd, hdc) ;
DeleteDC (hdcMem) ;
xCenter += cxMove ;
yCenter += cyMove ;
if ((xCenter + cxRadius >= cxClient) || (xCenter - cxRadius <= 0))
cxMove = -cxMove ;
if ((yCenter + cyRadius >= cyClient) || (yCenter - cyRadius <= 0))
cyMove = -cyMove ;
return 0 ;
case WM_DESTROY:
if (hBitmap)
