GDI/图象编程

开发平台：
Visual C++

DEMO1_2.C：源码内容
							  1 /****************************************************************/
  2 /*         Demo1_2   ---  The use of WM_PAINT                   */
  3 /****************************************************************/
  4 
  5 #include <windows.h>
  6 #include "demo1_2.h"
  7 
  8 int  PASCAL  WinMain(HANDLE, HANDLE, LPSTR, int);
  9 long FAR PASCAL MainWndProc(HWND, unsigned, WORD, LONG);
 10 
 11 
 12 /****************************************************************/
 13 /*                      WinMain()                               */
 14 /****************************************************************/
 15 
 16 int PASCAL WinMain(HANDLE hInstance, HANDLE hPrevInstance,
 17                    LPSTR lpszCmdLine, int nCmdShow)
 18 {
 19    WNDCLASS wclass;
 20    MSG      msg;
 21    HWND     hWnd;
 22    char     szName[] = "Demo1_2";
 23 
 24    if (!hPrevInstance)
 25     {
 26         wclass.style         = CS_HREDRAW | CS_VREDRAW;
 27         wclass.lpfnWndProc   = MainWndProc;
 28         wclass.cbClsExtra    = 0;
 29         wclass.cbWndExtra    = 0;
 30         wclass.hInstance     = hInstance;
 31         wclass.hIcon         = LoadIcon(NULL, IDI_APPLICATION);
 32         wclass.hCursor       = LoadCursor(NULL, IDC_ARROW);
 33         wclass.hbrBackground = GetStockObject(WHITE_BRUSH);
 34         wclass.lpszMenuName  = szName;
 35         wclass.lpszClassName = szName;
 36 
 37         if (!RegisterClass (&wclass))
 38            return (FALSE);
 39     }
 40 
 41     hWnd = CreateWindow(
 42                 szName,
 43                 "The Use of WM_PAINT",
 44                 WS_OVERLAPPEDWINDOW,
 45                 CW_USEDEFAULT,
 46                 CW_USEDEFAULT,
 47                 CW_USEDEFAULT,
 48                 CW_USEDEFAULT,
 49                 NULL,
 50                 NULL,
 51                 hInstance,
 52                 NULL );
 53 
 54     if (!hWnd)
 55         return (FALSE);
 56 
 57     ShowWindow(hWnd, nCmdShow);
 58     UpdateWindow(hWnd);
 59 
 60     while (GetMessage(&msg, NULL, NULL,NULL))
 61        {
 62            TranslateMessage(&msg);
 63            DispatchMessage(&msg);
 64        }
 65     return (msg.wParam);
 66 }
 67 
 68 
 69 /****************************************************************/
 70 /*                      MainWndProc()                           */
 71 /****************************************************************/
 72 
 73 long FAR PASCAL MainWndProc(HWND hWnd, unsigned message,
 74                             WORD wParam, LONG lParam)
 75 {
 76    HDC           hDC;
 77    PAINTSTRUCT   ps;
 78    HANDLE        hFont;
 79    char          szString[30];
 80    static int    i = 1;
 81    static char   szMovePos[48];
 82    static char   szLBDownPos[48];
 83    static char   szLBUpPos[48];
 84    static char   szRBDownPos[48];
 85    static char   szRBUpPos[48];
 86 
 87    switch (message)
 88     {
 89         case WM_COMMAND:
 90                 switch(wParam)
 91                   {
 92                     case IDM_MESG :
 93                          hDC = GetDC(hWnd);
 94                          wsprintf(szString,
 95                                  "This is message %d", i++);
 96                          TextOut(hDC, 10, 10, szString,
 97                                  strlen(szString));
 98                          ReleaseDC(hWnd, hDC);
 99                          break;
100 
101                     case IDM_EXIT :
102                          DestroyWindow (hWnd);
103                          break;
104                   }
105                 break;
106 
107         case WM_MOUSEMOVE :
108                 wsprintf(szMovePos, "WM_MOUSEMOVE: %3d %3d",
109                          LOWORD(lParam), HIWORD(lParam));
110                 InvalidateRect(hWnd, NULL, FALSE);
111                 break;
112 
113 
114         case WM_LBUTTONDOWN :
115                 wsprintf(szLBDownPos, "WM_LBUTTONDOWN: %3d %3d",
116                          LOWORD(lParam), HIWORD(lParam));
117                 InvalidateRect(hWnd, NULL, FALSE);
118                 break;
119 
120         case WM_LBUTTONUP :
121                 wsprintf(szLBUpPos, "WM_LBUTTONUP: %3d %3d",
122                          LOWORD(lParam), HIWORD(lParam));
123                 InvalidateRect(hWnd, NULL, FALSE);
124                 break;
125 
126         case WM_RBUTTONDOWN :
127                 wsprintf(szRBDownPos, "WM_RBUTTONDOWN: %3d %3d",
128                          LOWORD(lParam), HIWORD(lParam));
129                 InvalidateRect(hWnd, NULL, FALSE);
130                 break;
131 
132         case WM_RBUTTONUP :
133                 wsprintf(szRBUpPos, "WM_RBUTTONUP: %3d %3d",
134                          LOWORD(lParam), HIWORD(lParam));
135                 InvalidateRect(hWnd, NULL, FALSE);
136                 break;
137 
138         case WM_PAINT :
139                 hDC = BeginPaint(hWnd, &ps);
140 
141                 hFont = GetStockObject(SYSTEM_FIXED_FONT);
142                 SelectObject(hDC, hFont);
143 
144                 TextOut(hDC, 10, 30, szMovePos,
145                         strlen(szMovePos));
146                 TextOut(hDC, 10, 50, szLBDownPos,
147                         strlen(szLBDownPos));
148                 TextOut(hDC, 10, 70, szLBUpPos,
149                         strlen(szLBUpPos));
150                 TextOut(hDC, 10, 90, szRBDownPos,
151                         strlen(szRBDownPos));
152                 TextOut(hDC, 10, 110, szRBUpPos,
153                         strlen(szRBUpPos));
154 
155                 EndPaint(hWnd, &ps);
156                 break;
157 
158       case WM_DESTROY :
159                 PostQuitMessage(0);
160                 break ;
161 
162       default :
163                 return (DefWindowProc(hWnd, message, wParam, lParam));
164     }
165    return (NULL);
166 }

						