C++模拟滚轮完整单击一次的事件

INPUT Input = {0};
		Input.type = INPUT_MOUSE;
		Input.mi.dwFlags = MOUSEEVENTF_MIDDLEDOWN | MOUSEEVENTF_MIDDLEUP | MOUSEEVENTF_ABSOLUTE;
		Input.mi.dx = pt.x;
		Input.mi.dy = pt.y;
		::SendInput(1, &Input, sizeof(INPUT));