CreateWindow-example.c

#include <windows.h>

HWND hwnd;
LRESULT CALLBACK WndProc(HWND hwnd, UINT Msg, WPARAM wParam, LPARAM lParam);

int CALLBACK wWinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, wchar_t * lpCmdLine, int nCmdShow)
{
  	MSG         Msg;
    WNDCLASSEX  WndClsEx = {0};

    WndClsEx.cbSize        = sizeof (WNDCLASSEX);
    WndClsEx.style         = CS_HREDRAW | CS_VREDRAW;
    WndClsEx.lpfnWndProc   = WndProc;
    WndClsEx.hInstance     = hInstance;
    WndClsEx.hbrBackground = (HBRUSH)GetStockObject(WHITE_BRUSH);
    WndClsEx.lpszClassName = "ClassName";
    WndClsEx.hIconSm       = LoadIcon(hInstance, IDI_APPLICATION);

    RegisterClassEx(&WndClsEx);

    hwnd = CreateWindowEx(WS_EX_OVERLAPPEDWINDOW,
                          "ClassName",
                          "Window Title",
                          WS_OVERLAPPEDWINDOW,
                          100,
                          120,
                          600,
                          100,
                          NULL,
                          NULL,
                          hInstance,
                          NULL);

    ShowWindow(hwnd, nCmdShow);
    UpdateWindow(hwnd);

    while(GetMessage(&Msg, NULL, 0, 0))
    {
        TranslateMessage(&Msg);
        DispatchMessage(&Msg);
    }
	return 0;
}
LRESULT CALLBACK WndProc(HWND hwnd, UINT Msg, WPARAM wParam, LPARAM lParam)
{
    switch(Msg)
    {
    case WM_DESTROY:
        PostQuitMessage(WM_QUIT);
        break;
	case WM_PAINT:
		{
			/* */
	PAINTSTRUCT ps;
	HDC         hdc;
	RECT        rc;
	hdc = BeginPaint(hwnd, &ps);

	GetClientRect(hwnd, &rc);
	SetTextColor(hdc, 0);
	SetBkMode(hdc, TRANSPARENT);
	DrawText(hdc, "HELLO WORLD", -1, &rc, DT_CENTER|DT_SINGLELINE|DT_VCENTER);

	EndPaint(hwnd, &ps);
	/* */
            break;
		}
		break;
    default:
        return DefWindowProc(hwnd, Msg, wParam, lParam);
    }
    return 0;
}