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TouchList.length

This read-only property indicates the number of items (touch points) in a TouchList.

Syntax

var numTouches = touchList.length;

Return value

numTouches
The number of touch points in touchList.

Example

This code example illustrates the use of the TouchList interface's item method and the length property.

target = document.getElementById("target");

target.addEventListener('touchstart', function(ev) {

  // If this touchstart event started on element target, 
  // set touch to the first item in the targetTouches list;
  // otherwise set touch to the first item in the touches list
  var touch;

  if (ev.targetTouches.length >= 1)
     touch = ev.targetTouches.item(0);
  else
     touch = ev.touches.item(0);
}, false);

Specifications

Specification Status Comment
Touch Events – Level 2 Editor's Draft Non-stable version.
Touch Events Recommendation Initial definition.

Browser compatibility

Feature Chrome Edge Firefox (Gecko) Internet Explorer Opera Safari (WebKit)
Basic support 22.0 (Yes) 18.0 (18.0)[1]
52.0 (52.0)[2]
No support No support No support
Feature Android Android Webview Chrome for Android Edge Firefox Mobile (Gecko) Firefox OS IE Mobile Opera Mobile Safari Mobile
Basic support (Yes) (Yes) (Yes) (Yes) 6.0 (6.0) (Yes) 11 (Yes) (Yes)

[1] Touch events were implemented in Gecko 18.0, but removed again in 24.0 (Firefox 24.0 / Thunderbird 24.0 / SeaMonkey 2.21) on the desktop version of Firefox due to web compatibility issues (bug 888304).

[2] As of Gecko 52.0, touch events support has been fixed and reenabled in Windows desktop platforms.

© 2005–2018 Mozilla Developer Network and individual contributors.
Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-US/docs/Web/API/TouchList/length