如何使用InjectTouchInput特定的窗口？

我试图使用InjectTouchInput发送触摸事件到特定的窗口。 POINTER_INFO结构有hwndTarget字段，据我hwndTarget ，它指定目标窗口发送input。

但是当我尝试使用这个参数时，注入失败，代码为ERROR_INVALID_PARAMETER (87)

码：

 void MakePointerTouchInfo(POINTER_TOUCH_INFO& contact, int x, int y, int radius, int id, int orientation = 90, int pressure = 32000) { ZeroMemory(&contact, sizeof(POINTER_TOUCH_INFO)); contact.pointerInfo.pointerType = PT_TOUCH; contact.pointerInfo.ptPixelLocation.x = x; contact.pointerInfo.ptPixelLocation.y = y; contact.pointerInfo.pointerId = id; contact.touchFlags = TOUCH_FLAG_NONE; contact.pointerInfo.pointerFlags = POINTER_FLAG_DOWN | POINTER_FLAG_INRANGE | POINTER_FLAG_INCONTACT; contact.touchMask = TOUCH_MASK_NONE; } POINTER_TOUCH_INFO contacts[2]; // to start injection in separate thread. DWORD makeInjection_(LPVOID p) { InitializeTouchInjection(5, TOUCH_FEEDBACK_DEFAULT); MakePointerTouchInfo(contacts[0], 200, 300, 2, 1); MakePointerTouchInfo(contacts[1], 250, 300, 2, 6); HWND hwnd = hWnd; // if I don't set hwnd (default 0), it works contacts[0].pointerInfo.hwndTarget = contacts[1].pointerInfo.hwndTarget = hwnd; if (!InjectTouchInput(1, contacts)) { // //here it fails // LPWSTR str = new wchar_t[255]; auto t = GetLastError(); wsprintf(str, L"%d\n", t); OutputDebugString(str); } contacts[0].pointerInfo.pointerFlags = POINTER_FLAG_UPDATE | POINTER_FLAG_INRANGE | POINTER_FLAG_INCONTACT; contacts[1].pointerInfo.pointerFlags = POINTER_FLAG_UPDATE | POINTER_FLAG_INRANGE | POINTER_FLAG_INCONTACT; //drag them from/to each other for (int i = 0; i < 100; i++) { contacts[0].pointerInfo.ptPixelLocation.x += 1; contacts[1].pointerInfo.ptPixelLocation.x -= 1; bool s = InjectTouchInput(1, contacts); Sleep(10); } //release them contacts[0].pointerInfo.pointerFlags = POINTER_FLAG_UPDATE; contacts[1].pointerInfo.pointerFlags = POINTER_FLAG_UPDATE; bool success2 = InjectTouchInput(1, contacts); return 0; 

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