button Property

Internet Development Index

Sets or retrieves the mouse button pressed by the user.


event.button [ = iWhichButton ]

Possible Values

iWhichButtonInteger that specifies or receives one of the following values.
0Default. No button is pressed.
1Left button is pressed.
2Right button is pressed.
3Left and right buttons are both pressed.
4Middle button is pressed.
5Left and middle buttons both are pressed.
6Right and middle buttons are both pressed.
7All three buttons are pressed.

The property is read/write. The property has a default value of 0.

Expressions can be used in place of the preceding value(s), as of Microsoft® Internet Explorer 5. For more information, see About Dynamic Properties.


The property is read-only in Microsoft® Internet Explorer 4.0, and read/write in Internet Explorer 5 and later.

This property is used with the onmousedown, onmouseup, and onmousemove events. For other events, it defaults to 0 regardless of the state of the mouse buttons.

Standards Information

There is no public standard that applies to this property.

Applies To