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Gets the mouse button that caused an event.

Property of dom/MouseEventdom/MouseEvent


Note: This property is read-only.

var button = event.button;

Return Value

Returns an object of type NumberNumber

One of the following values -

  • 0 - The primary button (usually the left mouse button).
  • 1 - The auxiliary button (usually the middle/wheel mouse button).
  • 2 - The secondary button (usually the right mouse button).

Any value higher than 2 represents other less common buttons.

Related specifications

DOM Level 3 Events
Working Draft