关于这个内容，我参考了一篇文章：https://blog.csdn.net/bimabushihaodongxi/article/details/70942975
2022.07.29 更新
WM_MOUSEWHEEL 消息特殊处理：http://huidong.xyz/index.php?mode=2&id=448
总结一下吧，在窗口过程函数中把鼠标消息整合成一个 EasyX 的 ExMessage，就像下面这样，很浓缩了。
// 消息记录
switch (msg)
{
// EM_MOUSE
case WM_MOUSEMOVE:
case WM_MOUSEWHEEL:
case WM_LBUTTONDOWN:
case WM_LBUTTONUP:
case WM_LBUTTONDBLCLK:
case WM_MBUTTONDOWN:
case WM_MBUTTONUP:
case WM_MBUTTONDBLCLK:
case WM_RBUTTONDOWN:
case WM_RBUTTONUP:
case WM_RBUTTONDBLCLK:
{
ExMessage msgMouse = {};
msgMouse.message = msg;
msgMouse.x = GET_X_LPARAM(lParam);
msgMouse.y = GET_Y_LPARAM(lParam);
msgMouse.wheel = GET_WHEEL_DELTA_WPARAM(wParam);
msgMouse.shift = LOWORD(wParam) & 0x04 ? true : false;
msgMouse.ctrl = LOWORD(wParam) & 0x08 ? true : false;
msgMouse.lbutton = LOWORD(wParam) & 0x01 ? true : false;
msgMouse.mbutton = LOWORD(wParam) & 0x10 ? true : false;
msgMouse.rbutton = LOWORD(wParam) & 0x02 ? true : false;
// 有滚轮消息时，得到的坐标是屏幕坐标，需要转换
if (msgMouse.wheel)
{
POINT p = { msgMouse.x ,msgMouse.y };
ScreenToClient(g_vecWindows[indexWnd].hWnd, &p);
msgMouse.x = (short)p.x;
msgMouse.y = (short)p.y;
}
g_vecWindows[indexWnd].vecMessage.push_back(msgMouse);
}
break;