Enumerating and filtering

Enumerating, or listing, the objects in a collection in PowerShell does not need a specialized command. For example, if the results of Get-PSDrive were assigned to a variable, enumerating the content of the variable is as simple as writing the variable name and pressing Return:

PS> $drives = Get-PSDrive
$drives
Name     Used (GB) Free (GB) Provider   Root
----     --------- --------- --------   ----
Alias                        Alias 
C           319.37   611.60  FileSystem  C:\
Cert                         Certificate \ 
Env                          Environment 
...

ForEach-Object may be used where something complex needs to be done to each object.

Where-Object may be used to filter results.

The ForEach-Object command

ForEach-Object is most often used as a loop (of sorts). For example, the following command works on each of the results from Get-Process in turn:

Get-Process | ForEach-Object { 
    Write-Host $_.Name -ForegroundColor Green 
}

In the preceding example...