Non-standard
This feature is non-standard and is not on a standards track. Do not use it on production sites facing the Web: it will not work for every user. There may also be large incompatibilities between implementations and the behavior may change in the future.
The MouseEvent.which
read-only property indicates which button was pressed on the mouse to trigger the event. The standard alternatives to this property are MouseEvent.button
and MouseEvent.buttons
.
Syntax
var buttonPressed = instanceOfMouseEvent.which
Return value
A number representing a given button:
0
: No button1
: Left button2
: Middle button (if present)3
: Right button
For a mouse configured for left-handed use, the button actions are reversed. In this case, the values are read from right to left.
Specification
This is not part of any specification.
Browser compatibility
The compatibility table on this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request.
Desktop | Mobile | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
which | Chrome Full support 1 | Edge Full support 12 | Firefox
Full support
1
| IE Full support 9 | Opera Full support 10.6 | Safari Full support 3.1 | WebView Android Full support Yes | Chrome Android Full support Yes | Firefox Android
Full support
4
| Opera Android Full support 11 | Safari iOS Full support Yes | Samsung Internet Android Full support Yes |
Legend
- Full support
- Full support
- Non-standard. Expect poor cross-browser support.
- Non-standard. Expect poor cross-browser support.
- See implementation notes.
- See implementation notes.