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The output from the script is a text file called drives.log; you can see the results of running the script in The Drive object represents a disk drive or network share.. In the example f

the system using the Drives collection The output from the script is a text

file called drives.log; you can see the results of running the script in

The Drive object represents a disk drive or network share To use a Drive

object, you must reference it from an instance of the FileSystemObject

You can’t instantiate it directly using CreateObject() This also holds true

for the Drives, Files, File, Folders, Folder, and TextStream

objects In the example for the Drive object, you see how to get it from the

FileSystemObject and then use it to output information about the C:

Unlike the Dictionary and FileSystemObject, the Drive object has no

methods You can, however, use some of its properties to change the

characteristics of drives on your system (specifically the Volume label).

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 FileSystem



This returns a string that indicates the file system of a drive

The types that can be returned are FAT, NTFS, or CDFS. 

is a local drive, it returns "". 

Make sure to use the IsReady() method in your JScript code

before you attempt to access the properties of a drive The current

version of JScript suffers from a lack of good error handling

capabilities, so if an error occurs when you attempt to access a

drive, your JScript code just bombs out with an error Support for

enhanced error handling will be available in an upcoming JScript

version release from Microsoft.

 The Drive object enables you to retrieve all the details for a drive Here’s an

 // about a local or network drive. 



The drive.js script uses a FileSystemObject to get access to the

drives property, which is the Drives collection The Drives collection

can be indexed using a string much like the Dictionary You use this

capability to get a Drive object that corresponds to the argument that the

user passed on the command line Next, you output all the information about

the Drive by echoing its properties to the screen You can see the results of

running the drive.js script in Figure 3.5.

The File object represents a file stored on a local or network disk Using a

File object, you can retrieve all the properties of a file, you can open it to

read or write as text, and you can copy, move, or delete the file You can get

an instance of a File object from either a FileSystemObject or Folder

4—System; 8—Disk drive Volume label; 16—

Directory; 32—Archive; 64—Alias (like a link or shortcut); and 128—Compressed.

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at the destination, it is not overwritten unless

is read-only unless the force flag is specified

a file already exists at the destination, an error

ForReading—opens the file for reading only;

ForWriting—opens a file for writing;

ForAppending—opens a file and enables you

to write to the end of the file The format flag can be one of the following:

TristateUseDefault—indicates that the file should be opened using the system default;

TristateTrue—indicates that the file should

be opened as Unicode; TristateFalse—

indicates that the file should be opened as ASCII.

 The File object enables you to retrieve all the details for a file; here's an

 WScript.echo("File " + args(0) + " details:"); 

The first part of the example displays all of the information that we can

gather from the properties of a file object You’ll notice that we use a custom

function, ShowFileAttributes(), to decode and display the information

about the file attributes The body of ShowfileAttributes() is listed

This very simple script displays all the available information about a file,

including its size, name, attributes, and more First you instantiate a

FileSystemObject; you use it to call the

FileSystemObject.getFile() method, which returns a File object

Then you simply echo all the properties of the File object to the screen

Notice that, for simplicity’s sake, you’ve split out the code that checks the file

attributes into a separate function called ShowFileAttributes() The

results of the script are illustrated in Figure 3.6.

The Folder object represents a folder (or directory) on a local or network

disk Using a Folder object, you can retrieve all the properties of a folder,

you can retrieve a collection of the files or folders within it, and you can copy,

move, or delete the folder You can get an instance of a Folder object from

either a FileSystemObject or Drive object.

 Attributes 

 This enables you to set or get the attributes of a

folder It is a numeric value that uses a logical combination of the following values: 0—Normal; 1—

ReadOnly; 2—Hidden; 4—System; 8—Disk drive Volume label; 16—Directory; 32—Archive;

64—Alias (like a link or shortcut); and 128—

In this sample script, first you instantiate a FileSystemObject, and then

you get a Folder object by calling the

FileSystemObject.getFolder() method At that point, you simply echo

folder properties to the screen The output of the folder.js script is

Earlier in this chapter, you learned about the various objects that you can

access through the FileSystemObject For each object, there is a

collection object that holds a group of objects For example, many Drive

objects can be in a Drives collection These collections are used simply to

represent a group of file system components If you want to find out how to

access these collections, review the FileSystemObject and its methods

All the collections have the same basic capabilities; they can return a count

of entries and enable the user to access individual entries Consequently,

you’re not going to look at each one separately because they are so similar

There is one exception to the rule; the Folders collection has a method that

enables you to add a folder whereas the Drives and Files collections do



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not In any case, after you learn how to use one collection, it is easy to use

any of the others.

For this example, you use the various collection objects to display

information about a disk drive First, you instantiate a FileSystemObject

so that you can access the Drives collection Next, you get the specific

drive that you want by using the argument as the index into the Drives

collection, and then you check the state of the drive using the isReady

property It’s important to check the isReady property; if you don’t check it,

your script might experience errors if the drive is, for example, a CD-ROM

drive that doesn’t currently contain a CD-ROM disk You get the root folder of

the drive using the rootFolder property and display all the subfolders of

the rootFolder by iterating through the subFolders property Finally, you

display all the files in the root folder of the drive by iterating through the

rootFolder.files collection Figure 3.8 shows the output from the

The TextStream object makes it easy to perform sequential access

functions with a text file You can use it to read or skip through a file, to write

to a file, and to track your position within a file Like many of the other

objects, you can’t instantiate it directly Instead, you have to use either a

FileSystemObject or a File object to create a TextStream.

 TextStream Object Properties 

This indicates whether the file pointer is positioned

immediately before the end-of-line marker. 





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WriteLine(string)



This writes a string to an open text file and then

Here’s an example that uses the FileSystemObject to instantiate a

TextStream object that’s used to output a file to the console with line

This example uses an instance of the FileSystemObject to create a

TextStream object by calling FileSystemObject.openTextFile()

The openTextFile() method returns a new TextStream object, and then

a loop reads lines from the TextStream until you reach the end of it, at

which point the TextStream.atEndOfStream property returns True

Figure 3.9 shows the output of the textstrm.js script.

instantiate a FileSystemObject , Drives , Drive , Folders , and then Folder

Using VBScript, it’s possible to dynamically resize an array by using the

of an array that I dynamically resize?

However, it’s very inefficient because every element in the array is affected by

ReDim The Dictionary object is implemented differently; consequently, it’s more efficient to use when you need a dynamically resizable array of elements.

 2. Use the FileSystemObject to write a script that takes a filename and echoes it to

Write a script that takes a folder name as input and writes a list of the files in the folder

to a nicely formatted text file For an advanced exercise, modify the program to go through the subfolders of the folder while outputting file information to a text file.



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 Day 4: The WSH Object Model 

The Windows Scripting Host scripting environment provides basically two sets of

objects: objects that are included with the scripting engine and WSH-specific objects You learned about the scripting objects on Day 3, "The Scripting Object Model," and in this chapter you'll learn about the WSH scripting objects.

This chapter assumes basic familiarity with Microsoft OLE and ActiveX OLE

is the standard for embedding objects inside of applications; you may have

used it to put a a spreadsheet excerpt inside a document ActiveX (or the

Component Object Model [COM]) is essentially the object standard that

underlines OLE—it provides the fundamental capabilities to instantiate and

use objects If you'd like more information, refer to the Microsoft web site

Like the scripting objects, the WSH objects provide very powerful tools that enable you

to access and change the Windows environment For example, they enable you to

change network drive mappings and read or modify the Windows registry In this

chapter, you'll cover all the WSH scripting objects; you'll see reference information

describing their properties and methods and examples using each object Like Day 3, this chapter is intended to give you a basic familiarity with the objects In subsequent

chapters, you'll develop examples that use WSH objects combined with standard

The WSH objects are provided by the Windows Scripting Host environment

They are extremely powerful and provide you with the capabilities that you

need to perform many standard tasks The standard objects include

Wscript, WshArguments, WshShell, WshNetwork, WshShortcut,

WshUrlShortcut, WshCollection, WshEnvironment, and

WshSpecialFolders The WSH objects are depicted in Figure 4.1.

The name of the object corresponds to the functionality provided by the

object For example, the WshShell object enables you to manipulate the

Windows shell The WshNetwork object enables you to change connections

to the network The purposes of the others should be fairly self-explanatory

given the naming convention Later you’ll find more specifics about each of

the objects, and you’ll see code examples that illustrate the use of each

object Bear in mind that later in the book you’ll have more complete

examples that show you how you can use groups of these objects together

to perform really useful tasks.

The root WSH object is the Wscript object It’s always available when a

script is running in the scripting host, so you don’t have to create an instance

of the object It’s not really a root object from an inheritance perspective, but

it’s easy to think of it as such because it plays a central role for WSH scripts

The Wscript object provides the capability to retrieve information about a

the script’s runtime environment and arguments It also provides the

capability to create objects or retrieve them from files Finally, it provides the

capability to echo information to the screen and to quit with an exit code You

will almost certainly use the Wscript object, if only to create objects or echo

information to the screen!









When you access the object, you use the object name Wscript Unlike the

other objects that are described in this chapter, you don’t have to initialize a

new object instance for it The Wscript or cscript program takes care of

those details for you.

up event handling for the object that you create You must specify the PROGID of the object to create it, such as Excel.Application, and you can optionally specify the prefix

of event-handling methods that you implement.

CreateObject() or GetObject() methods.

 Echo(arg1, arg2, ) 



This enables you to echo information to the screen If Wscript is executing the script, the output pops up in a dialog box If cscript is executing the script, the output is echoed to the screen, such

as the DOS ECHO batch file command.

The Wscript object is a very powerful object that you use all the time in

your WSH scripts Here’s an example using WSH that shows how you can

create and manipulate ActiveX objects exposed by Microsoft Excel to

programmatically create a spreadsheet:

In this script, you’re using the ever present Wscript object to create an

instance of the Excel.Application object Most people recognize that

Excel is the popular spreadsheet provided by Microsoft as part of their Office

Suite However, many people are unaware that Excel provides a very

powerful OLE automation interface that enables you to develop external

programs that control Excel Basically, any external program that can use

OLE automation objects can use Excel programmatically You can do it from

Visual Basic, Delphi, or C++ In your example, you’re controlling it from a

WSH script implemented using the VBScript language You could also do it

using the JScript language in a WSH script; any WSH scripting engine

should be able to access OLE automation objects such as the objects

You begin with the Excel.Application object, and then you call a few

methods and change some Excel properties For more information about the

Excel object model, refer to the programming information provided by

Microsoft The results of running the script using cscript Wscript.vbs

from the command line are illustrated in Figure 4.2.

The WshArguments object provides you with a collection of the arguments

for the current script You can use arguments to customize the execution of

your script at runtime For example, you might define a script that runs a

special backup routine For the backup script, you might want to define

source and destination device arguments That’s one simple example; when

you are creating your script, keep in mind the portions of your script for which

you want to use arguments That helps you to create scripts that you can

write once and reuse over and over without any modification.









To access the WshArguments object, you don’t need to create an instance

using CreateObject() It’s immediately available to a running script from

the Wscript.Arguments property.

is also the default property for the WshArguments object.

 In the preceding showparams.vbs script, you begin by setting the variable

args to the Wscript.Arguments property The Wscript.Arguments

property returns a WshArguments object Next, you loop through the



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