Learn PowerShell Core 6.0

The parameter attribute

With a function keyword, the name, and a script block, you are well on your way to creating great reusable code. The next step to improve code quality is to introduce proper parameters.

The parameter attribute decorates each one of your parameters, and allows you to set several options. The most common one is the declaration of a mandatory parameter, as seen in the next code sample:

# The basic parameter attributeparam(    [Parameter()]    $YourParameter)# A mandatory parameterparam(    [Parameter(Mandatory)]    $YourParameter)# A help message for mandatory parametersparam(    [Parameter(        Mandatory,        HelpMessage = 'This is visible when needed'        )]    $YourParameter)# Hidden Parametersfunction fun{    param    (        [Parameter(DontShow)] $CatchMeIfYouCan ...