Touch: identifier property

Limited availability

This feature is not Baseline because it does not work in some of the most widely-used browsers.

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.

Value

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

Examples

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

Specifications

Specification
Touch Events
# dom-touch-identifier

Browser compatibility