创建一个基本的 Win32 窗口

1 #include <Windows.h>
2
3 //Forward declarations
4 bool InitMainWindow(HINSTANCE, int);
5 LRESULT CALLBACK MsgProc(HWND, UINT, WPARAM, LPARAM);
6
7 //Constants
8 const int WIDTH = 800;
9 const int HEIGHT = 600;
10
11 HWND hwnd = NULL;
12
13 int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine, int nCmdShow)
14 {
15     //Initialize the window
16     if (!InitMainWindow(hInstance, nCmdShow))
17     {
18         return 1;
19     }
20
21     //Main message loop
22     MSG msg = {0};
23     while (WM_QUIT != msg.message)
24     {
25         if (PeekMessage(&msg, NULL, 0, 0, PM_REMOVE))
26         {
27             TranslateMessage(&msg);
28             DispatchMessage(&msg);
29         }
30     }
31
32     return static_cast<int>(msg.wParam);
33 }
34
35 bool InitMainWindow(HINSTANCE hInstance, int nCmdShow)
36 {
37     WNDCLASSEX wcex;
38     wcex.cbSize = sizeof(wcex);
39     wcex.style = CS_HREDRAW | CS_VREDRAW;
40     wcex.cbClsExtra = 0;
41     wcex.cbWndExtra = 0;
42     wcex.lpfnWndProc = MsgProc;
43     wcex.hInstance = hInstance;
44     wcex.hIcon = LoadIcon(NULL, IDI_APPLICATION);
45     wcex.hCursor = LoadCursor(NULL, IDC_ARROW);
46     wcex.hbrBackground = (HBRUSH)GetStockObject(WHITE_BRUSH);
47     wcex.lpszClassName = "Basic Win32 Window";
48     wcex.lpszMenuName = NULL;
49     wcex.hIconSm = LoadIcon(NULL, IDI_WINLOGO);
50
51     //Register window class
52     if (!RegisterClassEx(&wcex))
53     {
54         return false;
55     }
56
57     //Create window
58     hwnd = CreateWindow(
59         "Basic Win32 Window",
60         "Win32 Window",
61         WS_OVERLAPPED | WS_SYSMENU | WS_CAPTION,
62         GetSystemMetrics(SM_CXSCREEN) / 2 - WIDTH / 2,
63         GetSystemMetrics(SM_CYSCREEN) / 2 - HEIGHT / 2,
64         WIDTH,
65         HEIGHT,
66         (HWND)NULL,
67         (HMENU)NULL,
68         hInstance,
69         (LPVOID*)NULL);
70
71     if (!hwnd)
72     {
73         return false;
74     }
75
76     ShowWindow(hwnd, nCmdShow);
77
78     return true;
79 }
80
81 LRESULT CALLBACK MsgProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam)
82 {
83     switch (msg)
84     {
85     case WM_DESTROY:
86         PostQuitMessage(0);
87         return 0;
88
89     case WM_CHAR:
90         switch (wParam)
91         {
92         case VK_ESCAPE:
93             PostQuitMessage(0);
94             return 0;
95         }
96         return 0;
97     }
98
99     return DefWindowProc(hwnd, msg, wParam, lParam);
100 }