Reading command line arguments

PowerShell:
Reading command line arguments

How to

PowerShell reads command line arguments using the $args array or parameters. $args is quick for one-off scripts; parameters are better for robust tools.

Using `$args`

# myscript.ps1
Write-Host "You entered the following arguments:"
$args

Run with .\myscript.ps1 Hello PowerShell, outputs:

You entered the following arguments:
Hello PowerShell

Using Parameters

# myscriptparam.ps1
param (
    [string]$Name,
    [int]$Age
)
Write-Host "Hello, $Name! You are $Age years old."

Run with .\myscriptparam.ps1 -Name Sarah -Age 32, outputs:

Hello, Sarah! You are 32 years old.

Deep Dive

PowerShell’s modern approach to command line arguments is akin to a legacy from its predecessors like cmd and Bash. However, it amplifies flexibility and precision.

Historical Context

Years back, batch files and shell scripts accessed arguments with numbered variables (like %1, %2). PowerShell refined this with $args and named parameters for more clarity and control.

Alternatives

There are alternatives, like parsing raw input with Read-Host or accepting piped input. However, $args and parameters are more seamless for automated tasks and scripts.

Implementation Details

$args is a simple array, good for arbitrary input. Parameters, with their attributes and types, can validate input and even prompt the user, making scripts self-documenting and less prone to errors.

PowerShell:Reading command line arguments