Touch.identifier

This is an experimental technology
Because this technology's specification has not stabilized, check the compatibility table for the proper prefixes to use in various browsers. Also note that the syntax and behavior of an experimental technology is subject to change in future versions of browsers as the spec changes.

The Touch.identifier returns a value uniquely identifying this point of contact with the touch surface. This value remains consistent for every event involving this finger's (or stylus's) movement on the surface until it is lifted off the surface.

Syntax

JavaScript
touchItem.identifier;

Return value

A DOMString that represents the unique ID of the Touch object.

Example

JavaScript
someElement.addEventListener('touchmove', function(e) { 
// Iterate through the list of touch points that changed 
// since the last event and print each touch point's identifier. 
  for (var i=0; i < e.changedTouches.length; i++) { 
    console.log("changedTouches[" + i + "].identifier = " + e.changedTouches[i].identifier); 
  } 
}, false);

Specifications

Specification Status Comment
Touch Events – Level 2 Editor's Draft No change.
Touch Events Recommendation Initial definition.

Browser compatibility

Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari (WebKit)
Basic support 22.0 18.0 (18.0) Not supported Not supported Not supported
Feature Android Android Webview Chrome for Android Firefox Mobile (Gecko) Firefox OS IE Mobile Opera Mobile Safari Mobile
Basic support (Yes) (Yes) (Yes) 6.0 (6.0) (Yes) 11 (Yes) (Yes)

License

© 2016 Mozilla Contributors
Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-us/docs/web/api/touch/identifier

API Property Read-only Reference touch