Variables

We use variables to store all types of values. PowerShell is an Object Oriented Scripting Language. PowerShell works with objects, and these objects can have attributes and methods. An attribute is a property or a description.

A variable is a unit of memory in which values are stored. In PowerShell, variables are represented by text strings that begin with a dollar sign ($), such as $a, $b, or $my_var. Variable names aren’t case-sensitive, and can include spaces and special characters. Yes! you read it right. can include spaces and special characters. But, variable names that include special characters and spaces are difficult to use and should be avoided.

We need not to define the type of variable. PowerShell automatically decides the type of variable.

Working with variables

To get a list of all the variables in your PowerShell session, type Get-Variable.

We can assign values manually. For example:

$name = "James"
$names = "Robert", "John", "Mary"

We can use variables to store result of a command.

For example:

$Processes = Get-Process
$Services = Get-Service

To display the value of a variable, type the variable name, preceded by a dollar sign ($).

PS C:\> $name
James
PS C:\> $names
Robert
John
Mary
PS C:\> $Processes

Handles  NPM(K)    PM(K)      WS(K)     CPU(s)     Id  SI ProcessName
-------  ------    -----      -----     ------     --  -- -----------
    381      28    16928      39288       0.13  20672   1 ApplicationFrameHost
   1315     116    64912     107460     123.41  18036   1 AppMarket
    130      10     1704       6856              5192   0 armsvc
.
.
.
    279      14     3776      10388             13800   0 WUDFHost
    248      14     3660       9260             14244   0 WUDFHost
    913      56    56568      31100       0.45  13964   1 YourPhone


PS C:\>

To change the value of a variable, assign a new value to the variable.

To delete the value of a variable, use the Clear-Variable cmdlet or change the value to $null. To delete the variable, use Remove-Variable or Remove-Item.

Clear-Variable -Name my_var

Remove-Variable -Name my_var