XHTML/XHTML Objects
In HTML, objects could only be attached to specific image tags or object tags. This changed with XHTML, where these images or resources can be attached to almost any tag.
Images
editImages can be explicitly specified with the img
tag. XHTML also provides the ability to attach images to span
tags as described blow. A significant change from HTML is that there is no longer an alt attribute to describe the image if it cannot load; instead, the content enclosed within the tag pair (if any) is displayed if the resource cannot be loaded.
The src
attribute contains a URL to the resource in question. If the resource can be loaded, it replaces the tag with the object itself. Otherwise, the content within the tags is displayed instead. This attribute is used in combination with srctype
, which provides information about the resource in question. Typically, it may appear as "image/png" or "image/jpeg".
The encoding
attribute identifies the character set of the resource, if it is a text document.
An image can also be used as a navigation map with the usemap
attribute, which refers to an id of a navigation list within the element. The <li
tags within the navigation list will have the shape
and coords
elements to specify the details of the navigation map.
Objects
editArbitrary objects within XHTML are declared by the <object
tag. The object itself is loaded from the src
attribute. If the object is loaded successfully, it will be loaded with the parameters enclosed within the object tag. However, a failure will cause the enclosed to be rendered instead.
The following attributes are used:
Attribute | Description |
---|---|
src | The source of the object. |
srctype | The type of object, such as "image/png", "audio/mpeg", or "application/x-java-applet". Other types are possible. |
id | A unique identifier for the object, if applicable. |
archive | Provides additional URLs which are related to the object. |
content-length | Provides the size of the object in question. |
declare="declare" | If present, causes the object to be loaded after the document finished loading. |
Parameters
editWithin the object tag, parameters can be included to provide information to the loaded object.
The <param>
tag uses two base attributes; name
which is the name of the parameter, and value
which is the content of the parameter. In addition, the param tag can also use valuetype
if the parameter's value is a reference (ref) or object (object). Be default, the value type of the parameter is data.
Standby
editContent within a <standby>
tag is displayed when an object is loading, but hasn't yet finished.
Scripting objects
editThe <handler>
tag indicates a script that handles events within the document. If the browser is unable to load the handler, it will process the content enclosed within the handler tag pair instead, including additional nested handler elements.
With the handler element, the type
attribute is mandatory. It describes the scripting language used, such as "text/javascript".