How do I detect if a device is touch-enabled in C# for a WinForms app (Not WPF).

* I found information on `GetSystemMetrics`. But I can't find how to use this in C#.
* I tried using `System.Windows.Input.Tablet` class. But it's not coming up in C#, even though I am using .NET Framework 4.5.
* I tried using `System.Windows.Devices`. But it's not coming up in C#, even though I am using .NET Framework 4.5.
* I have also checked [Detect whether a Windows 8 Store App has a touch screen](https://stackoverflow.com/q/12664228/) and [How to detect a touch enabled device (Win 8, C#.NET)](https://stackoverflow.com/q/14898376/), which would seem to make this question a duplicate. However, neither of these answers my question.