MICROSOFT_PRESS_EBOOK_PROGRAMMING_WINDOWS_8_APPS_WITH_HTML_CSS_AND_JAVASCRIPT_PDF

FIGURE 9-1 The PointerEvents example display (screen shot cropped a bit to show detail).
Within the handlers for all of the MSPointer* events, the eventArgs object contains a whole roster of
properties. One of them, pointerType, identifies the type of input: touch (2), pen (3), and mouse (4). This
property lets you implement different behaviors for different input methods, if desired. Each event
object also contains a unique pointerId value that identifies a stroke or a path for a specific contact
point, allowing you to correlate an initial MSPointerDown event with subsequent events. When we look at
gestures in the next section, we’ll also see how we use the pointerId of MSPointerDown to associate a
gesture with a pointer.
The complete roster of properties that come with the event is actually far too much to show here, as
it contains many of the usual DOM properties along with many pointer-related ones from an object
type called MSPointerEvent. The best way to see what shows up is to run some code like the Input
DOM pointer event handling sample (a canvas drawing app), set a breakpoint within a handler for one
of the events, and examine the event object. The table on the following page describes some of the
properties (and a few methods) relevant to our discussion here.
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