↑
Main Page

HTML page

</head>

<body>

<p>Type the name of the <acronym title=”Multipurpose Internet Mail

Extension”>MIME</acronym>

you want to check and click the Find Plugin button.</p>

</body>

</html>

The HTML page listed previously allows you to enter a MIME type into a text box and click a button

to determine if a MIME type is registered. If so, you can tell whether it has a browser plugin. The

findPlugin()

function retrieves the value from the text box and first checks to see if the

navigator

.mimeTypes

collection exists. If it does, then the function continues on to see if the MIME type is

defined. If it is, you can tell whether it has a plugin installed.

You can extract the methodology to test for a plugin that handles a particular MIME type into a separate

function:

function hasPluginForMimeType(sMimeType) {

if (navigator.mimeTypes) {

return navigator.mimeTypes[sMimeType].enabledPlugin != null;

} else {

return false;

}

Then, you can check for the existence of a given plugin like so:

if (hasPluginForMimeType(“application/x-shockwave-flash”)) {

alert(“The Flash plugin is installed.”);

} else {

alert(“The Flash plugin is not installed.”);

}

It’s also possible to retrieve a list of all registered plugins without using the MIME types. The

navigator.plugins

collection contains all plugins, indexed by name and by number, available for

the given browser. Each entry in the collection is a plugin object equivalent to the one referenced by

enabledPlugin

for each MIME type. So, if you know the name of a plugin (equivalent to its

name

property), you can access it directly:

var oFlashPlugin = navigator.plugins[“Shockwave Flash”];

Otherwise, you can iterate through the plugins to print out the information about each one. A simple

page can also be used to do this:

<html>

<head>

<title>Plugins Example</title>

</head>

<body>

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