Windows PowerShell Methods

This section concentrates on pure PowerShell techniques. I will explain how to take those first few tentative steps on your journey to master PowerShell. If you review my techniques below, then you will get an idea of the range of PowerShell methods available. My aim is to help you develop an approach to writing PowerShell cmdlets (scripts), which suits your learning style.

Topics for PowerShell Methods

I have sequenced these PowerShell techniques. Thus if you are new to PowerShell I suggest that you start by going to the Control Panel, Progrmas and 'Turn Windows feature on' (or with Vista, downloading PowerShell from Microsoft’s site).

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Contents of My PowerShell Method Pages

Each topic has its own 'how to' instructions and also 'Learning points'. As a result you will be able to modify my examples to suit your situation.

Basic Techique: Filtering the OutPut

There are two main methods of filtering the output of a PowerShell command, 'Where-Object' and the -Filter parmeter.

Find .txt Files Using the -Filter Parameter

# PowerShell -Filter Technique
Get-ChildItem "C:\Program Files" -recurse -Filter *.txt

Note 1: # (hash) means: ‘Here follows a comment’.

Find .txt Files Using a Where-Object Statement
Not all PowerShell cmdlets support the -Filter parameter, thus it's useful to employ Where-Object.

# PowerShell Where-Object Technique
Clear-Host
Get-ChildItem "C:\Program Files" -recurse | Where {$_.extension -eq ".txt"}

Note 2: Here is PowerShell's signature tune, the Pipe(|). This means the output of Get-ChildItem, becomes the input of the Where clause. After a while piping becomes second nature in PowerShell

Note 3: I frequently employ Clear-Host in my examples to provide a fresh slate and thus avoid confusion.

Where-Object is a good place to start »

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PowerShell Looping

To me, there is still something magical about scripting loops. Of course it's this ability to iterate that speeds up scripts and makes it worthwhile taking the trouble to write scripts.

Disk Drive WMI Example

#Example: ForEach Loop
$HardDrive= Get-WmiObject Win32_LogicalDisk
ForEach ($Drive in $HardDrive ) { "Drive = " + $Drive.Name}

Note 1: Observe the two elements. (Condition) {Pay load}

Pure Math Examples
This example uses the 'Do…While' loop.

#Calculate the 13 times multiplication table
$n = 13
$i =1
Do {($i * $n); $i++ } While ($i -le 20)

Note 2: * means multiply

Maths and Text Together
This is not a particularly elegant example, more the rough-and-ready thinking you go through as you learn how to forge PowerShell commands to produce the result you want.

$n = 13
$i =1
Do {Write-Host $i x $n = ($i * $n); $i++ } While ($i -le 20)

Note 3: See how easily PowerShell combines text (x, =) with the numeric variables $n and $i.

See much more on PowerShell Loops »

See more Windows PowerShell sections

• PowerShell Home • Introduction • Dreams • 3 Key Commands • Free Permissions Analyzer

• PowerShell Real-life Examples • PowerShell Techniques • PowerShell Syntax • Contact

• PowerShell ISE • PowerShell 2.0 • PowerShell v 3.0 • PowerShell v 4.0 • PowerShell v 4.0

Please email me if you have a better example script. Also please report any factual mistakes, grammatical errors or broken links, I will be happy to correct the fault.

Windows PowerShell Methods