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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.

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

See also

MimeType, document.embeds


description

A human-readable description of the plug-in. The text is provided by the plug-in developers.

Property of

Plugin

Read-only

Implemented in

JavaScript 1.1


filename

The name of a plug-in file on disk.

Property of

Plugin

Read-only

Implemented in

JavaScript 1.1

Description

The filename property is the plug-in program's file name and is supplied by the plug-in itself. This name may vary from platform to platform.

Examples

See the examples for Plugin.


length

The number of elements in the plug-in's array of MimeType objects.

Property of

Plugin

Read-only

Implemented in

JavaScript 1.1


name

A string specifying the plug-in's name.

Property of

Plugin

Read-only

Implemented in

JavaScript 1.1

Security

JavaScript 1.1: This property is tainted by default. For information on data tainting, see the Client-Side JavaScript Guide.

Description

The plug-in's name, supplied by the plug-in itself. Each plug-in should have a name that uniquely identifies it.


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Last Updated: 11/16/98 12:57:05

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