Question

I’m looking at the developers reference for IE10 (http://msdn.microsoft.com/en-us/library/ie/hh673549(v=vs.85).aspx) and I’m basically trying to figure out how touch works in IE10.

I have been unable to find if there is a property that tells you how many touches are on the screen. I’m basically looking for a JavaScript property of some sort that I could check.

The only way that you seem to be able to do that is to trap the MSPointerDown and MSPointerUp events and keep count of how many unique pointers you have based on the pointerId.

Answer 1

You can check the following section of the above document that you listed… http://msdn.microsoft.com/en-us/library/ie/hh673557(v=vs.85).aspx#maxtouchpoints

// To test for touch capable hardware 
if(navigator.msMaxTouchPoints) { ... }

// To test for multi-touch capable hardware
if(navigator.msMaxTouchPoints && navigator.msMaxTouchPoints > 1) { ... }

// To get the maximum number of points the hardware supports
var touchPoints = navigator.msMaxTouchPoints;