Is there a way to programmatically tell if a system is touch enabled?

I'm trying to figure out how to programmatically tell if a Windows 7 machine has touch enabled. Are there any touch API's (managed or unmanaged) that can help me achieve this? Or perhaps something开发者_StackOverflow社区 in the registry I can check?

---

Use GetSystemMetrics to look for SM_MAXIMUMTOUCHES settings.

Nonzero if there are digitizers in the system; otherwise, 0.

SM_MAXIMUMTOUCHES returns the aggregate maximum of the maximum number of contacts supported by every digitizer in the system. If the system has only single-touch digitizers, the return value is 1. If the system has multi-touch digitizers, the return value is the number of simultaneous contacts the hardware can provide.