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MouseEvent altKey Property

❮ DOM Events ❮ MouseEvent

Example

Find out whether or not the "ALT" key was pressed when a mouse button is clicked:

if (event.altKey) {
  alert("The ALT key was pressed!");
} else {
  alert("The ALT key was NOT pressed!");
}
Try it Yourself »

Definition and Usage

The altKey property returns a Boolean value that indicates whether or not the "ALT" key was pressed when a mouse event was triggered.

Note: On some Mac keyboards, the "ALT" key is displayed as "Option" or "Opt".

Note: This property is read-only.


Browser Support

Property
altKey Yes Yes Yes Yes Yes

Syntax

event.altKey

Technical Details

Return Value: A Boolean, indicating whether the "ALT" key was pressed when the mouse event occured.

Possible values:

  • true - The alt key was pressed
  • false - The alt key was not pressed
DOM Version: DOM Level 2 Events

Related Pages

HTML DOM reference: MouseEvent ctrlKey Property

HTML DOM reference: MouseEvent metaKey Property

HTML DOM reference: MouseEvent shiftKey Property


❮ DOM Events ❮ MouseEvent