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Cross-browser detection

Plugin

Version-Independent Version-Specific Names

Name

Real Player G2

rmocx.RealPlayer rmocx.RealPlayer G2 Control.1

G2 Control

Quicktime

Quicktime.Quicktime Quicktime.Quicktime.1

Windows Media Player

WMPlayer.OCX

WMPlayer.OCX.7

WMPlayer.OCX.8

To make use of the ActiveX control name, try to create the given object using an

ActiveXObject

. For

example:

function detectFlashInIE() {

try {

new ActiveXObject(“ShockwaveFlash.ShockwaveFlash”);

return true;

} catch (oError) {

return false;

}

This function’s purpose is to determine if the Flash Player is installed. To do so, it tries to create the

ActiveXObject

with the name

ShockwaveFlash.ShockwaveFlash

. If this is successful, the next line

executes and the function returns

true

. If the object can’t be created, the error is caught and the function

returns

false

. This same basic algorithm can be used for any plugin with an ActiveX wrapper.

Cross-browser detection

Unfortunately, you have no easy way to establish cross-browser plugin detection in a generic way. In

order to accurately detect if a plugin is available, you must know both the MIME type and the ActiveX

control name. Most of the time, developers just create specific detection functions that include both

pieces of information, such as the following:

function detectFlash() {

if (navigator.mimeTypes.length > 0) {

return navigator.mimeTypes[“application/x-shockwave-flash”].enabledPlugin

!= null;

} else if (window.ActiveXObject) {

try {

new ActiveXObject(“ShockwaveFlash.ShockwaveFlash”);

return true;

} catch (oError) {

return false;

}

This method of plugin detection works only in Internet Explorer 5.0 and higher for

Windows.

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