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Plugin

A plug-in module installed on the client.

Client-side object
Implemented in	JavaScript 1.1

Created by

Plugin objects are predefined JavaScript objects that you access through the navigator.plugins array.

Description

A Plugin object is a plug-in installed on the client. A plug-in is a software module that the browser can invoke to display specialized types of embedded data within the browser. The user can obtain a list of installed plug-ins by choosing About Plug-ins from the Help menu.

Each Plugin object is itself array containing one element for each MIME type supported by the plug-in. Each element of the array is a MimeType object. For example, the following code displays the type and description properties of the first Plugin object's first MimeType object.

myPlugin=navigator.plugins[0]
myMimeType=myPlugin[0]
document.writeln('myMimeType.type is ',myMimeType.type,"<BR>")
document.writeln('myMimeType.description is ',myMimeType.description)

The preceding code displays output similar to the following:

myMimeType.type is video/quicktime
myMimeType.description is QuickTime for Windows

The Plugin object lets you dynamically determine which plug-ins are installed on the client. You can write scripts to display embedded plug-in data if the appropriate plug-in is installed, or display some alternative information such as images or text if not.

Plug-ins can be platform dependent and configurable, so a Plugin object's array of MimeType objects can vary from platform to platform, and from user to user.

Each Plugin object is an element in the plugins array.

When you use the EMBED tag to generate output from a plug-in application, you are not creating a Plugin object. Use the document.embeds array to refer to plug-in instances created with EMBED tags. See the document.embeds array.

Property Summary

Property Description
description
A description of the plug-in.

filename
Name of the plug-in file on disk.

length
Number of elements in the plug-in's array of MimeType objects.

name
Name of the plug-in.

Property	Description
`description`	A description of the plug-in.
`filename`	Name of the plug-in file on disk.
`length`	Number of elements in the plug-in's array of `MimeType` objects.
`name`	Name of the plug-in.

Method Summary

This object inherits the watch and unwatch methods from Object.

Examples

Example 1. The user can obtain a list of installed plug-ins by choosing About Plug-ins from the Help menu. To see the code the browser uses for this report, choose About Plug-ins from the Help menu, then choose Page Source from the View menu.

Example 2. The following code assigns shorthand variables for the predefined LiveAudio properties.

var myPluginName = navigator.plugins["LiveAudio"].name
var myPluginFile = navigator.plugins["LiveAudio"].filename
var myPluginDesc = navigator.plugins["LiveAudio"].description

Example 3. The following code displays the message "LiveAudio is configured for audio/wav" if the LiveAudio plug-in is installed and is enabled for the "audio/wav" MIME type:

var myPlugin = navigator.plugins["LiveAudio"]
var myType = myPlugin["audio/wav"]
if (myType && myType.enabledPlugin == myPlugin)
   document.writeln("LiveAudio is configured for audio/wav")

Example 4. The following expression represents the number of MIME types that Shockwave can display:

navigator.plugins["Shockwave"].length

Example 5. The following code displays the name, filename, description, and length properties for each Plugin object on a client:

document.writeln("<TABLE BORDER=1><TR VALIGN=TOP>",
   "<TH ALIGN=left>i",
   "<TH ALIGN=left>name",
   "<TH ALIGN=left>filename",
   "<TH ALIGN=left>description",
   "<TH ALIGN=left># of types</TR>")
for (i=0; i < navigator.plugins.length; i++) {
   document.writeln("<TR VALIGN=TOP><TD>",i,
      "<TD>",navigator.plugins[i].name,
      "<TD>",navigator.plugins[i].filename,
      "<TD>",navigator.plugins[i].description,
      "<TD>",navigator.plugins[i].length,
      "</TR>")
}
document.writeln("</TABLE>")

The preceding example displays output similar to the following:

i
name
filename
description
# of types

0
QuickTime Plug-In
d:\nettools\netscape\nav30\Program\
plugins\NPQTW32.DLL
QuickTime Plug-In for Win32 v.1.0.0
1

1
LiveAudio
d:\nettools\netscape\nav30\Program\
plugins\NPAUDIO.DLL
LiveAudio--Netscape Navigator sound playing component
7

2
NPAVI32 Dynamic Link Library
d:\nettools\netscape\nav30\Program\
plugins\npavi32.dll
NPAVI32, avi plugin DLL
2

3
Netscape Default Plugin
d:\nettools\netscape\nav30\Program\
plugins\npnul32.dll
Null Plugin
1