Guy's Scripting Ezine 43 - File System Object

Contents for Guy's Scripting Ezine 43 - File System Object

• This week's secret
• Example 1 Build a folder, create a file
• Example 2 Writing data into a file
• Summary FSO

This week’s secret

I love magicians.  In particular I admire (from a distance) those card-sharps that you see scurrying around at low grade race tracks.  One of the best tricks that I ever saw, was performed by a hustler who threw some sticks and felt into the air; miraculously, they unfolded to form a card table. Even more spectacularly, the hustler had dealt the first three cards before his table hit the ground.  What on earth has magic got to do with VBScript?  Well I love self contained scripts which magically unfurl to conjure files out of thin air.

This week's script will produce a folder, fashion a file and then fill that file with text.  There is no need for you to tinker with variables to make this week's code work.  However, if you wish, then you could uncomment one line and the folder will disappear - magic!

This week's project

If you master the File Scripting Object, and it's not difficult, then you can extend your VBScripts to include, reading .csv files and writing WMI output to .txt files.  We will start by creating folders and adding files, then we are ready to write to those files.

CreateObject("Scripting.FileSystemObject") is the key command that conjures up a file object.  We can manipulate this FSO with VBScript commands.  What I want to do this week is master the basic FSO methods, for example .CreateFolder .WriteLine.

Naturally, we start with building a folder to house our files. Once we have created a file we can then start writing lines of text. More likely, we need to store the output data, for example, when a WMI script interrogates the operating system. In the case of import spreadsheets, it's the reverse. By that I mean we want to read the cells into the script and then use that data to modify user objects in Active Directory.

Example 1 Build a folder and create a file

Scenario.  You need a new folder with a new file.  Perhaps this is in preparation for writing WMI (Windows Management Information) data.

Instructions

1. Copy and paste the script into notepad.
2. Optionally, examine and amend the variables strFile and strDirectory
3. Save the file with .vbs extension e.g. NewFolder.vbs
4. Double click and observe the message boxes.
5. Open Windows Explorer and check to see if your script created a new file.

Learning Points

Note 1:  CreateObject("Scripting.FileSystemObject") is the command that builds objFSO.  The significance is that with objFSO we make the File System Object, then we can use its magic to create a folder and finally, create a file.

Note 2:  We can also delete a folder.  The actual reason for including .DeleteFolder in the test script is to prevent error 800A003A - File already exists.

Example 2 Writing data into a file that you have created.

Scenario:  Even I admit that FSO is rarely the sole purpose of VBScript.  However, my point is that when you master the .Methods and objects which FSO offers, then your scripts benefit from the increased flow of data.   Write data output to text files, or open spreadsheets and use the data to configure your Active Directory objects.

Learning Points

Note 1:  This script uses the construction:  If.. Exists,  Then, Else, ..End If.  My reasoning for this construction is to cater for you running the script several times without getting errors and without deleting the folder.  Tell the truth, I just love any excuse to experiment with the 'IF' statement.

Note 2:  The main point of this script is to open the file = special.txt and then write in the strText.  To achieve this goal we use the .OpenTextFile method.  This method relies on the statement: Const ForAppending = 8.

Note 3:  The action method is .WriteLine.  In 'real' scripts this would be repeated several times, for example .WriteLine for each value the WMI extracts from the operating system.  (Free disk space, Operating System Version, or DHCP leases.

Note 4:  Spot how the .Close method shuts the file gracefully.

Summary

FSO, (File System Object) has a surprisingly rich set of methods.  I use FSO when reading from spreadsheets and for writing WMI data to disk.  It is worth learning, not only how to create folders and files, but also how to write data into that file.

See more on FSO - Whole Section Here

Guy Thomas recommends Computer Training Software. 

Their topics and material are ideal for getting you started with VBScript.  The videos are easy to follow and you can control the pace.  Try their free demo material and then see if you want to buy the full package. See more about VB Script Training CD.

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