Event Handlers
Event handlers are where JavaScript gets its power. By looking for specific user
actions, JavaScript can confirm or act on input immediately, without waiting for
server introduction, since user activity within an HTML page is limited to mouse
movement and input on form elements.
onBlur Blurs occur when a select, text
or textarea field on a form loses focus. Event handler of select,
text, textarea. See EVENT HANDLERS onChange and onFocus.
onChange A change event happens when a select,
text, or textarea element on a form is modified before losing focus.
Event handler of select, text, textarea. See EVENT HANDLERS
onBlur, onFocus.
onClick Occurs when an object, such as a button or check
box, is clicked. Event handler of button, checkbox, radio,
link, reset, submit.
onFocus A form element receives focus by tabbing to or
clicking the input area with the mouse. Selecting within a field results in a select
event. Event handler of select, text, textarea. See EVENT
HANDLERS onBlur and onChange.
onLoad A load event is created when Navigator finishes
loading a window or all frames within a <frameset> tag. Event handler
of window. See onUnload EVENT HANDLER.
onMouseOver Occurs when the mouse pointer is placed over
a link object. To function with the status or defaultStatus
properties, the event handler must return true. Event handler of link.
onSelect A select event is triggered by selecting some
or all of the text in a text or textarea field. Event handler of
text, textarea.
onSubmit Triggered by the user submitting a form. The
event handler must return true to allow the form to be submitted to the
server. Conversely, it returns false to block the form's submission. Event
handler of form. See submit OBJECT and METHOD.
onUnload Occurs when exiting a document. For proper operation,
place the onUnload handler in the <body> or <frameset>
tags. Event handler of window. See onLoad EVENT HANDLER.
Last Words
On June 26, 1997, a language standard for Internet scripting was announced by
ECMA, "an international, Europe-based industry association founded in 1961 and
dedicated to the standardization of information and communication systems" (from
the ECMA site, which seemed reluctant to divulge just what ECMA stands for). The
standard will be known as ECMA-262, or ECMA Script. ECMA Script was derived from
Netscape's JavaScript specification.
JavaScript is on its way to standardization.
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