Operate the data (Intermediate)

Data Operations are critical routine administrative tasks and, with the release of Windows PowerShell Version 3.0, we have made some improvements regarding the handling of data in the console.

Getting ready

There are a few new operators introduced in PowerShell Version 3.0. For example, the In and NotIn operators.

How to do it...

Try executing the following code:

1. The following command checks the availability of 1 in the reference set and returns True in this case:

   PS C :\> 1 -In (1,2,3)
   True
   

2. The following command checks for an exact counter match for the Admin keyword in the reference set and returns True in this case:

   PS C :\> "Admin" -NotIn "Administrator"
   True
   

How it works...

The following table mentions the syntaxes for these operators:

Operator	Syntax	Description
-In	<Test-value> -In <Reference-values>	This operator returns a Boolean value as output. If any test value is present in the reference values set, it returns True, else False.
-NotIn	<Test-value> -NotIn <Reference-values>	This operator also returns a Boolean value as output. If any test value is not present in the reference values set, it returns True, else False.

There's more…

There are a few new parameters introduced with the following CMDLETs:

Get-Content

The Get-Content CMDLET retrieves content from a specified file.

• -Tail <Int32>: To retrieve the number of lines from the file, use the Tail parameter with the Get-Content CMDLET. It retrieves the number of lines supplied to this parameter. For example:

  PS C :\> Get-Content -Path C:\PSTest.txt -Tail 10
  

  The preceding command statement retrieves the last 10 lines from C:\PSTest.txt.

Tip

You can use the –Last instead of the Tail parameter; it is an alias of this parameter.

Tee-Object

The Tee-Object CMDLET stores output in a file or variable and throws to the pipeline.

• -Append [<SwitchParameter>]: If any file already exists and you try to supply it with Tee-Object, it overrides the content by default. To avoid this, you can use the –Append parameter with the Tee-Object CMDLET. For example:

  PS C:\>Get-ChildItem -Path C:\PSBooks -Recurse | Tee-Object -File C:\BookList.txt –Append
  

  The preceding command statement gets the list of PowerShell books and appends it to BookList.txt.