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TouchEvent.altKey

A Boolean value indicating whether or not the alt (Alternate) key is enabled when the touch event is created. If the alt key is enabled, the attribute's value is true. Otherwise, it is false.

This property is Read only .

Syntax

var altEnabled = touchEvent.altKey;

Return value

altEnabled
true if the alt key is enabled for this event; and false if the alt is not enabled.

Example

This example illustrates how to access the TouchEvent key modifier properties: TouchEvent.altKey, TouchEvent.ctrlKey, TouchEvent.metaKey and TouchEvent.shiftKey.

In following code snippet, the touchstart event handler logs the state of the event's modifier keys.

someElement.addEventListener('touchstart', function(e) {
   // Log the state of this event's modifier keys
   console.log("altKey = " + e.altKey);
   console.log("ctrlKey = " + e.ctrlKey);
   console.log("metaKey = " + e.metaKey);
   console.log("shiftKey = " + e.shiftKey);
}, 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.

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Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-US/docs/Web/API/TouchEvent/altKey