Home > Articles

Scripting and Objects

This chapter is from the book

Locating and Using Unusual Objects

Several powerful, commonly used objects provided with Windows are documented by Microsoft in the Windows Scripting reference documents, and I'll discuss most of these in Chapters 4 through 10 and in Appendix C, "WSF and WSC File Format Reference." If you're new to scripting, these will be enough to get you started, so you may just want to skip ahead to Chapter 4.

In addition to these standard objects, many developers and companies provide add-in objects for free or for sale. You can find many of these listed at http://www.microsoft.com/com/tech/activex.asp and on the many Web sites devoted to ActiveX and to scripting. Some of these sites are listed on pages 41-42.

There is, however, a wealth of objects already on your computer: Hundreds of COM objects are supplied with Windows, and hundreds more are added if you install applications such as Word, Excel, and Visio. Many were designed just for the use of specific application programs and are of no use to script authors. Others are general-purpose objects for use by scripts and by compiled programs. How can you tell what objects are installed on your computer and of those, which are useful for scripting? To be honest, identifying useful objects is tricky business. But if you enjoy detective work, read on.

To get an idea of what I mean by "hundreds of objects," take a look at the Windows Registry.

CAUTION

Improper changes to the Windows Registry can make your computer nonfunctional. There is no undo command in the Registry Editor, so be very careful not to make any changes while examining the Registry.

To view the Registry, click Start, Run, type regedit, and press Enter. Expand the entry for HKEY_CLASSES_ROOT and scroll down past the .xxx-format entries into the entries that spell out names like "something dot something," as shown in Figure 3.4. Most of the entries from here down represent object classes; you can tell which ones do by the presence of a CLSID or CurrVer key under the object name.

Figure 3.41Figure 3.4 COM object classes are listed in the Registry under HKEY_CLASSES_ROOT, after the .xxx entries. Objects have an associated CLSID entry.

In Figure 3.4, the FaxControl.FaxControl.1 entry has a CLSID entry, so it is an object. A CLSID (or class ID) is a very long, essentially random number that object authors use to give their object a unique "fingerprint." A CurrVer entry, such as the one found under FaxControl.FaxControl is used when there's a chance more than one version of the class program might be installed on your computer. The CurrVer value tells Windows where to look to find the class information for the most recent version of the object. Find that entry, and you'll find the object's CLSID.

The first step in scouting out new and interesting objects is to peruse the Registry for names that sound interesting. For this example, I'll follow up the FaxControl.FaxControl.1 object from Figure 3.4.

When you've found a CLSID value for a potentially interesting object, locate the matching value under My Computer\HKEY_CLASSES_ROOT\Clsid, where you'll find the information Windows uses to locate and run the program file that actually manages the object.

Figure 3.5 shows the class information for FaxControl.FaxControl.1. The InprocServer32 entry shows the actual program module (usually a DLL or OCX file) that manages the object. In this case, the program is \WINDOWS\system32\Setup\fxsocm.dll. The name of this object and the location of its DLL make it sound like it might be used for setting up the Fax service. But how?

The first thing that you have to check is whether the object is even suitable for use in script programs; some aren't. The first test, then, is to see whether you can create an object in your chosen scripting language. Use the server.object name that you found under HKEY_CLASSES_ROOT. In VBScript, it would look like this:

set obj = CreateObject("FaxControl.FaxControl.1")
WScript.echo "CreateObject worked!"

Figure 3.5Figure 3.5 Class ID information for the FaxControl.FaxControl.1 object.

If this script produces an error message, the object can't be used in scripts. If it runs without an error message, as it did when I tested FaxControl.FaxControl.1, the object has passed the first hurdle.

TIP

On http://www.helpwinxp.com/hood, I've listed all the undocumented objects provided with Windows XP that pass this test—to scout for interesting objects, start with that listing.

Now comes the hard part: extracting information about the object's methods and properties. In some cases, Microsoft or the object's creator will have supplied a help file describing the object. See if the Clsid registry values list has a help file ending in .hlp or .chm. If it does, at a command prompt type

start pathname\helpfile.xxx

where pathname\helpfile.xxx is the full path to the help file listed in the Registry. This may show you how the object works. In the case of FaxControl.FaxControl.1, there is no help file.

If no help file is named, don't give up. Because COM objects are designed to be used by many different programming languages, they have to record the types of values their properties and methods use—numeric, string, date, and so on—and they have to make this information available to any program that asks. You may be able to burrow into the object's program file to find this information.

The easiest way to do this is with an object browser, a program that's designed to do just this sort of burrowing. Microsoft provides one with many of its applications. If you have Microsoft Word, Excel, or PowerPoint, the Object Browser is included as part of the Macro Editor. Start the application and click Tools, Macro, Visual Basic Editor. Then click View, Object Browser. If you have the full developer's version of Visual Basic installed, run it and click View, Object Browser.

To view information for a questionable class, you'll need to tell Word (or Visual Basic, and so on) to look into the class's program file. To do this, click Tools, References. Click Browse and locate the DLL or OCX file you found in the Registry. Click Open, and the library will appear as a checked item in the Available References list, as shown in Figure 3.6.

Figure 3.6Figure 3.6 Selecting an object class type library to view in the Object Browser.

When the object type is listed and checked under Available References, click OK.

Then, select the class name from the library list in the upper-left corner of the Object Browser window, as shown in Figure 3.7. Choose object types in the left panel, and the browser will display the object's methods, procedures, and predefined constants in the right panel under "Members." You can select the objects in this list one by one, and in the bottom panel, the browser will display the method or procedure's arguments, if any, and any explanatory text it can dig up.

Figure 3.7Figure 3.7 Viewing a class's type information in the Object Browser.

If you don't have any of the applications I've mentioned, another tool, called the OLE/COM Object Viewer, is provided as part of Visual C++ as well as with the Windows XP and Windows 2000 Resource Kits. You can also download it from http://www.microsoft.com by searching for "OLE/COM Object Viewer."

The OLE/COM Object Viewer is much more difficult to use than the Object Browser. Here are some tips for using this viewer:

  • Try to find the object of interest under Object Classes, All Objects. I've found that not all the objects I'm interested in are listed there. For example, Scripting.Dictionary is present, whereas Scripting.FileSystemObject is missing. If you can't find it there, look under Type Libraries.

  • Double-click the library or object to view its class information. This information is designed for COM object programmers, not end users, so it's going to be tough to understand.

  • Typedef items list some predefined constant values used by all the objects provided by the server.

  • Coclass items define the objects that the class server can create. If you view the contents of a coclass item, you'll find the class's predefined constants, properties, and methods.

You should also search the Internet for references to the object name (for example, search for FaxControl.FaxControl.1 or FaxControl.FaxControl) or the program file itself. I've found that google.com is a great place to start. Be sure to search both the Web and Groups directories. Many programmers haunt the comp.xxx groups, and you may find an archived discussion about the object.

Although either object browser can show you what sorts of values the methods and properties expect and return, it can't tell you what these values mean, so you'll have to experiment to find out if and how you can use them. In the case of FaxControl.FaxControl.1, the Object Browser showed two properties and two methods, as listed in Reference List 3.4.


Reference List 3.4 Properties and Methods of the FaxControl.FaxControl Object.

IsFaxServiceInstalled

Property; returns a Boolean value.

IsLocalFaxPrinterInstalled

Property; returns Boolean value.

InstallFaxService

Method; returns no value and takes no arguments.

InstallLocalFaxPrinter

Method; returns no value and takes no arguments.


This sounds pretty straightforward. There are no arguments to supply to these methods, so there's no detective work required there. Also, the names sound pretty self-explanatory. This object lets you know whether the Fax service and the Fax Printer are installed, and it can install them. But does it work?

Here's a sample script I wrote to check:

set obj = CreateObject("FaxControl.FaxControl.1")
WScript.echo "IsFaxServiceInstalled =", obj.IsFaxServiceInstalled
WScript.echo "IsLocalFaxPrinterInstalled =", obj.IsLocalFaxPrinterInstalled

The results when I ran it on a Windows XP computer that had a modem but did not have the fax service set up were

IsFaxServiceInstalled = 0
IsLocalFaxPrinterInstalled = 0

When I ran the script

set obj = CreateObject("FaxControl.FaxControl.1")
obj.InstallFaxService

Windows Setup asked for my Windows XP CD disk and installed the Fax service and printer. The first script's output became this:

IsFaxServiceInstalled = -1
IsLocalFaxPrinterInstalled = -1

Here, -1 means True, (any nonzero value means True) so the object really does the job you'd expect it to. Here's a script that can automatically be sure a user's Windows XP system has the Fax service as well as a fax and printer installed:

set obj = CreateObject("FaxControl.FaxControl.1")

if not obj.IsFaxServiceInstalled then
  WScript.echo "Installing Fax Service..."
  obj.InstallFaxService
elseif not obj.IsLocalFaxPrinterInstalled then
  WScript.echo "Reinstalling Fax Printer..."
  obj.InstallLocalFaxPrinter
else
  WScript.echo "Fax printer is ready to go."
end if

This works like a charm. Of course, it's easier to do this same thing from the Windows XP user interface in the Printers and Faxes folder. Nevertheless, this is a good example of the functionality you can find by digging into the many objects that come with Windows, and it shows the kinds of scripts you can write to manage Windows computers so that other users don't have to poke around with the Control Panel themselves.

InformIT Promotional Mailings & Special Offers

I would like to receive exclusive offers and hear about products from InformIT and its family of brands. I can unsubscribe at any time.

Overview


Pearson Education, Inc., 221 River Street, Hoboken, New Jersey 07030, (Pearson) presents this site to provide information about products and services that can be purchased through this site.

This privacy notice provides an overview of our commitment to privacy and describes how we collect, protect, use and share personal information collected through this site. Please note that other Pearson websites and online products and services have their own separate privacy policies.

Collection and Use of Information


To conduct business and deliver products and services, Pearson collects and uses personal information in several ways in connection with this site, including:

Questions and Inquiries

For inquiries and questions, we collect the inquiry or question, together with name, contact details (email address, phone number and mailing address) and any other additional information voluntarily submitted to us through a Contact Us form or an email. We use this information to address the inquiry and respond to the question.

Online Store

For orders and purchases placed through our online store on this site, we collect order details, name, institution name and address (if applicable), email address, phone number, shipping and billing addresses, credit/debit card information, shipping options and any instructions. We use this information to complete transactions, fulfill orders, communicate with individuals placing orders or visiting the online store, and for related purposes.

Surveys

Pearson may offer opportunities to provide feedback or participate in surveys, including surveys evaluating Pearson products, services or sites. Participation is voluntary. Pearson collects information requested in the survey questions and uses the information to evaluate, support, maintain and improve products, services or sites, develop new products and services, conduct educational research and for other purposes specified in the survey.

Contests and Drawings

Occasionally, we may sponsor a contest or drawing. Participation is optional. Pearson collects name, contact information and other information specified on the entry form for the contest or drawing to conduct the contest or drawing. Pearson may collect additional personal information from the winners of a contest or drawing in order to award the prize and for tax reporting purposes, as required by law.

Newsletters

If you have elected to receive email newsletters or promotional mailings and special offers but want to unsubscribe, simply email information@informit.com.

Service Announcements

On rare occasions it is necessary to send out a strictly service related announcement. For instance, if our service is temporarily suspended for maintenance we might send users an email. Generally, users may not opt-out of these communications, though they can deactivate their account information. However, these communications are not promotional in nature.

Customer Service

We communicate with users on a regular basis to provide requested services and in regard to issues relating to their account we reply via email or phone in accordance with the users' wishes when a user submits their information through our Contact Us form.

Other Collection and Use of Information


Application and System Logs

Pearson automatically collects log data to help ensure the delivery, availability and security of this site. Log data may include technical information about how a user or visitor connected to this site, such as browser type, type of computer/device, operating system, internet service provider and IP address. We use this information for support purposes and to monitor the health of the site, identify problems, improve service, detect unauthorized access and fraudulent activity, prevent and respond to security incidents and appropriately scale computing resources.

Web Analytics

Pearson may use third party web trend analytical services, including Google Analytics, to collect visitor information, such as IP addresses, browser types, referring pages, pages visited and time spent on a particular site. While these analytical services collect and report information on an anonymous basis, they may use cookies to gather web trend information. The information gathered may enable Pearson (but not the third party web trend services) to link information with application and system log data. Pearson uses this information for system administration and to identify problems, improve service, detect unauthorized access and fraudulent activity, prevent and respond to security incidents, appropriately scale computing resources and otherwise support and deliver this site and its services.

Cookies and Related Technologies

This site uses cookies and similar technologies to personalize content, measure traffic patterns, control security, track use and access of information on this site, and provide interest-based messages and advertising. Users can manage and block the use of cookies through their browser. Disabling or blocking certain cookies may limit the functionality of this site.

Do Not Track

This site currently does not respond to Do Not Track signals.

Security


Pearson uses appropriate physical, administrative and technical security measures to protect personal information from unauthorized access, use and disclosure.

Children


This site is not directed to children under the age of 13.

Marketing


Pearson may send or direct marketing communications to users, provided that

  • Pearson will not use personal information collected or processed as a K-12 school service provider for the purpose of directed or targeted advertising.
  • Such marketing is consistent with applicable law and Pearson's legal obligations.
  • Pearson will not knowingly direct or send marketing communications to an individual who has expressed a preference not to receive marketing.
  • Where required by applicable law, express or implied consent to marketing exists and has not been withdrawn.

Pearson may provide personal information to a third party service provider on a restricted basis to provide marketing solely on behalf of Pearson or an affiliate or customer for whom Pearson is a service provider. Marketing preferences may be changed at any time.

Correcting/Updating Personal Information


If a user's personally identifiable information changes (such as your postal address or email address), we provide a way to correct or update that user's personal data provided to us. This can be done on the Account page. If a user no longer desires our service and desires to delete his or her account, please contact us at customer-service@informit.com and we will process the deletion of a user's account.

Choice/Opt-out


Users can always make an informed choice as to whether they should proceed with certain services offered by InformIT. If you choose to remove yourself from our mailing list(s) simply visit the following page and uncheck any communication you no longer want to receive: www.informit.com/u.aspx.

Sale of Personal Information


Pearson does not rent or sell personal information in exchange for any payment of money.

While Pearson does not sell personal information, as defined in Nevada law, Nevada residents may email a request for no sale of their personal information to NevadaDesignatedRequest@pearson.com.

Supplemental Privacy Statement for California Residents


California residents should read our Supplemental privacy statement for California residents in conjunction with this Privacy Notice. The Supplemental privacy statement for California residents explains Pearson's commitment to comply with California law and applies to personal information of California residents collected in connection with this site and the Services.

Sharing and Disclosure


Pearson may disclose personal information, as follows:

  • As required by law.
  • With the consent of the individual (or their parent, if the individual is a minor)
  • In response to a subpoena, court order or legal process, to the extent permitted or required by law
  • To protect the security and safety of individuals, data, assets and systems, consistent with applicable law
  • In connection the sale, joint venture or other transfer of some or all of its company or assets, subject to the provisions of this Privacy Notice
  • To investigate or address actual or suspected fraud or other illegal activities
  • To exercise its legal rights, including enforcement of the Terms of Use for this site or another contract
  • To affiliated Pearson companies and other companies and organizations who perform work for Pearson and are obligated to protect the privacy of personal information consistent with this Privacy Notice
  • To a school, organization, company or government agency, where Pearson collects or processes the personal information in a school setting or on behalf of such organization, company or government agency.

Links


This web site contains links to other sites. Please be aware that we are not responsible for the privacy practices of such other sites. We encourage our users to be aware when they leave our site and to read the privacy statements of each and every web site that collects Personal Information. This privacy statement applies solely to information collected by this web site.

Requests and Contact


Please contact us about this Privacy Notice or if you have any requests or questions relating to the privacy of your personal information.

Changes to this Privacy Notice


We may revise this Privacy Notice through an updated posting. We will identify the effective date of the revision in the posting. Often, updates are made to provide greater clarity or to comply with changes in regulatory requirements. If the updates involve material changes to the collection, protection, use or disclosure of Personal Information, Pearson will provide notice of the change through a conspicuous notice on this site or other appropriate way. Continued use of the site after the effective date of a posted revision evidences acceptance. Please contact us if you have questions or concerns about the Privacy Notice or any objection to any revisions.

Last Update: November 17, 2020