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昨天看WinMain函数的修饰符WINAPI,看得眩晕,今天专注于WinMain函数的过程也不轻松。为了弄明白一个窗口从创建到销毁的过程,也是大费周章。不过还好,能够看到自己建造的第一个最原始的窗口,总算有了点满足感。
创建一个窗口涉及了几个概念:HWND、WNDCLASS(WNDCLASSEX)、RegisterClass(RegisterClassEx)和CreateWindow(CreateWindowEx)。HWND就是Window Handle,它的实质就是一个指针,指向被创建的窗口对象;WNDCLASS(WNDCLASSEX)本身是一个结构体,代表着窗口对象,里面包含了与窗口对象紧密相关的属性;RegisterClass(RegisterClassEx)是用以注册窗口对象的函数;CreateWindow(CreateWindowEx)则是用以创建窗口对象,并且返回一个HWND。其中括号的内容是一一对应,就是说如果定义了WNCLASSEX,就必须用RegisterClassEx去注册,用CreateWindowEx去创建WNDCLASSEX定义的窗口对象。
创建一个看得见摸得着的窗口,主要有以下四步:
1、利用WNDCLASS(WNDCLASSEX)定义窗口对象;
2、调用RegisterClass(RegisterClassEx)函数注册窗口对象;
3、调用CreateWindow(CreateWindowEx)方法创建已经定义并且注册的窗口对象;
4、定义负责处理消息队列的Window Procedure。
以下为一个很简单的例子:
<div style="padding-right: 5.4pt; padding-left: 5.4pt; background: #e6e6e6; padding-bottom: 4px; width: 98%; padding-top: 4px;"> #include <windows.h>
LRESULT CALLBACK WindowProc(HWND hwnd,UINT msg,WPARAM wparam, LPARAM lparam);

int WINAPI WinMain(HINSTANCE hinstance,
HINSTANCE hprevinstance,LPSTR lpcmdline,int ncmdshow)
  {

 WNDCLASSEX winclass = {0};
HWND hwnd;
MSG msg;

winclass.cbSize = sizeof(WNDCLASSEX);
winclass.style = CS_HREDRAW | CS_VREDRAW;
winclass.lpfnWndProc = WindowProc;
winclass.hInstance = hinstance;
winclass.hbrBackground = (HBRUSH)GetStockObject(BLACK_BRUSH);
winclass.lpszClassName = "WinInit";

RegisterClassEx(&winclass);

hwnd = CreateWindowEx(NULL, "WinInit", "First Window",
WS_OVERLAPPEDWINDOW | WS_VISIBLE, 0, 0,
200, 200, NULL, NULL, hinstance, NULL);
for(;;)
 {
if (PeekMessage(&msg,NULL,0,0,PM_REMOVE))
 {
if (msg.message == WM_QUIT)
break;
TranslateMessage(&msg);
DispatchMessage(&msg);
}
}
return(msg.wParam);
}

LRESULT CALLBACK WindowProc(HWND hwnd,UINT msg,WPARAM wparam, LPARAM lparam)
  {
return DefWindowProc(hwnd, msg, wparam, lparam);
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