The which property refers to which key or mouse button was pressed or clicked.
The value returned for mouse events is a numeric value 1, 2, or 3, representing the left, middle, and right mouse buttons, respectively.
The value returned for keyboard events is a character representation for the key that was pressed.
<html>
<head>
<title>Using the which property of the event object</title>
</head>
<body>
<form>
This example uses the which property of the event object to determine
which mouse button is pressed.
<br><br>
<input type="radio" onClick = 'alert("Mouse button Number " + event.which + "was pressed.")'>
</form>
</body>
</html>
| 15.1.Event Object | ||||
| 15.1.1. | Event | |||
| 15.1.2. | event.data | |||
| 15.1.3. | event.height | |||
| 15.1.4. | event.layerX | |||
| 15.1.5. | event.layerY | |||
| 15.1.6. | event.pageX | |||
| 15.1.7. | event.pageY | |||
| 15.1.8. | event.screenX | |||
| 15.1.9. | event.screenY | |||
| 15.1.10. | event.target | |||
| 15.1.11. | event.type | |||
| 15.1.12. | event.which | |||
| 15.1.13. | event.width | |||
| 15.1.14. | Event.ABORT | |||
| 15.1.15. | Event.CHANGE | |||
| 15.1.16. | Add event handler to form | |||