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ActiveX Controls

All non-IE browsers ignore this code block because

“VBScript”

is unrecognized as a scripting lan-

guage; therefore, it’s safe to include this in your cross-browser pages (although it is still recommended

that this reside in the

<head/>

element to prevent rendering of the code as plain text). Another alterna-

tive is to place the VBScript into an external file (ending in .vbs) and load it into the page like this:

Because of the intricate workings of

fscommand()

, many developers simply choose to use

getURL()

for

JavaScript communication.

ActiveX Controls

In Internet Explorer on Windows, you can embed ActiveX controls in the page by using the

element. To do this, you need to know the class ID of the ActiveX control you wish to embed (this infor-

mation can be gleaned using the OLE/COM Object Viewer) and insert it as the

classid

attribute:

Not all ActiveX controls behave properly when embedded in a Web page. Indeed, some of them trigger

security warnings in Internet Explorer and possibly in software such as antivirus programs. However, a

few ActiveX controls were designed to work appropriately and safely in Web pages. One such compo-

nent is the tabular data control.

The tabular data control has no visual component to it, so it is an invisible object on your page. At first

glance, it hardly looks exciting — especially when compared to what you can do with Java and Flash.

At second glance, however, the tabular data control reveals some powerful functionality that allows

JavaScript to use database-like functionality.

Specifically, the tabular data control allows you to use a flat text file as if it were a database table. You tell

the control what the value delimiter character is, and it parses the text file into a series of rows and values.

To create a tabular data control on a page, you must use the class ID

“CLSID:333C7BC4-460F-11D0-

BC04-0080C7055A83”

(retrieved using the OLE/COM Object Viewer) and give the object an ID:

</object>

Next, you must specify the

DataURL

parameter, which indicates where the text file is located (this can be

either a relative or complete URL), and the

FieldDelim

parameter, which indicates what the delimiter is

between two values in the same row (most often this is a comma):

ActiveX-based plugins do not work on any non-Windows browser because ActiveX

is a Windows-specific technology. On Windows XP Service Pack 2, any ActiveX con-

trol that attempts to contact an outside server or is capable of accessing a local file

triggers a warning.

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