Javascript [Electronic resources] : The Definitive Guide (4th Edition) نسخه متنی

Availability

Netscape 3

Synopsis

navigator.plugins[i]
navigator.plugins['name']

Properties

description

A read-only string that contains a
human-readable description of the specified plugin. The text of this
description is provided by the creators of the plugin and may contain
vendor and version information as well as a brief description of the
plugin's function.

filename

A
read-only string that specifies the name of the file on disk that
contains the plugin program itself. This name may vary from platform
to platform. The name property is more useful than
filename for identifying a plugin.

length

Each Plugin object contains MimeType array elements that specify the
data formats supported by the plugin. As with all arrays, the
length property specifies the number of elements
in the array.

name

The name property of a Plugin object is a
read-only string that specifies the name of the plugin. Each plugin
should have a name that uniquely identifies it. The name of a plugin
can be used as an index into the
navigator.plugins[] array. You can use this fact
to determine easily whether a particular named plugin is installed in
the current browser:

var sw_installed = (navigator.plugins["Shockwave"] != null);

Elements

The array elements of the Plugin object are MimeType objects that
specify the data formats supported by the plugin.

Description

A

plugin is a software module that can be
invoked by Netscape to display specialized types of embedded data
within the browser window. In Netscape 3, plugins are represented by
the Plugin object. This object is somewhat unusual in that it has
both regular object properties and array elements. The properties of
the Plugin object provide various pieces of information about the
plugin, and its array elements are MimeType objects that specify the
embedded data formats that the plugin supports.

Plugin objects are obtained from the plugins[]
array of the Navigator object. navigator.plugins[]
may be indexed numerically when you want to loop through the complete
list of installed plugins, looking for one that meets your needs (for
example, one that supports the MIME type of the data you want to
embed in your web page). This array can also be indexed by plugin
name, however. That is, if you want to check whether a specific
plugin is installed in the user's browser, you might use code
like this:

document.write( navigator.plugins("Shockwave") ?
"<embed src="' height=100 width=100>" :
"You don't have the Shockwave plugin!" );

The name used as an array index with this technique is the same name
that appears as the value of the name property of
the Plugin.

Don't confuse the fact that Plugin objects are stored in an
array of the Navigator object with the fact that each Plugin object
is itself an array of MimeType objects. Because there are two arrays
involved, you may end up with code that looks like this:

navigator.plugins[i][j]            // The jth MIME type of the ith plugin
navigator.plugins["LiveAudio"][0]  // First MIME type of LiveAudio plugin 

Finally, note that while the array elements of a Plugin object
specify the MIME types supported by that plugin, you can also
determine which plugin supports a given MIME type with the
enabledPlugin property of the MimeType object.

See Also

Navigator, MimeType