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Programming the Marquee Element
Programming the Object Element
The Object element allows you to include controls and applets that extend
the browser. For example, you can create objects to embed graphs or even
other documents directly into the document. An object may have its own
properties, methods, and events, which the Object element exposes to scripts in the
same way that it exposes its own members.
Handling Property Conflicts
A conflict can occur between the object's members and the members of a generic Object element. For example, if the object exposes an
id property, it will collide with the
id property exposed on the Object element. When
this conflict occurs, referencing the id property references the element's
version, not the object's. For referencing the object's version of the
id property, all object elements expose an
object property. This property returns access to the
embedded object's members, as shown in the following code.
document.all.myObject.id // HTML element's id property
document.all.myObject.object.id // Embedded object's id property
Alternative HTML
The Object element can contain HTML code that is displayed in browsers
that do not support the Object element. The down-level contents are exposed
as an altHTML property of the Object element in HTML.
The altHTML property can be used to provide contents to the user if
the object fails to install. If the object fails to install, the alternative contents
replace the object on the page. In the following code, the value of the
Object element's altHTML property is the Paragraph element (the
<P> and </P> tags and the text between):
<OBJECT CLASSID="java:myClass">
<PARAM NAME="color" VALUE="red">
<P>
Either your browser does not support the Object element or an
error occurred while downloading the object.
</P>
</OBJECT>
Object Events
An object can fire its own custom events. You can bind a handler to such
an event using the <SCRIPT FOR= EVENT= > syntax or a
language-dependent mechanism, but not using an attribute in the element's tag. The Object
element exposes attributes for only those events that are predefined, not for events
that the embedded object may fire.
Objects that expose standard events such as mouse and keyboard
events can also take part in event bubbling. The object itself fires its standard
event, followed by the browser firing the event on every parent element. Generic
event handlers for standard events can test whether they originated in an object.
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Programming the Table Element
