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onbeforeupdate event

Fires on a databound object before updating the associated data in the data source object.

Syntax

HTML Attribute <element onbeforeupdate = "handler(event)">
Event Property object.onbeforeupdate = handler;
attachEvent Method object.attachEvent("onbeforeupdate", handler)
addEventListener Method object.addEventListener("beforeupdate", handler, useCapture)

 

Event information

Synchronous No
Bubbles Yes
Cancelable Yes

 

Event handler parameters

Standards information

There are no standards that apply here.

Remarks

If the HTMLOptionButtonElementEvents2::onbeforeupdate event is canceled, the HTMLOptionButtonElementEvents2::onafterupdate event does not fire.

Signals that the data contained in an object has changed.

To invoke this event, do one of the following:

  • Cause an object to receive focus, change the value of the object, and either cause the object to lose focus or force the document to unload.

The pEvtObj parameter is required for the following interfaces:

See also

Introduction to Data Binding