An object that contains properties and methods for inspecting and manipulating the browser event. This object can be referenced in JavaScript added to the event, either through Action Javascript or using Text Mode.

See Event (MDN Web Docs) for more details.


Fires when the control's value changes.


The onChange event fires when the value in the control changes. Controls like the dropdown box fire the onChange event when the user selects a new choice.

Some controls do not support the onChange event.

The onChange event is automatically wrapped in a setTimeout() function to delay the event for 1ms. This is done to prevent certain timing problems. In some cases, this delay can introduce other timing problems. You can insert a special directive to prevent your code from being wrapped in setTimeout():

{noSet TimeOut}

This directive must be added as the first line when editing the action using Text mode or as the first line of an Inline-Javascript action's definition. If Action Javascript is used, the Inline-Javascript action must be the first action in the list.