Get a PowerShell script's parameters and output certain aspects of each parameters. Utilizes the AST to get all its data.

Get-Parameters.ps1

function Get-Parameters {
    param(
        # Path to a .ps1 script
        [string]$Path
    )
    begin {}
    process {
        $ScriptPath = Get-Item -Path $Path
        $ScriptCommand = Get-Command $ScriptPath
        $ScriptBlock = $ScriptCommand.ScriptBlock
        $ScriptAst = $ScriptBlock.Ast
        $ScriptParamBlock = $ScriptAst.ParamBlock

        $ScriptParamBlock.Parameters | ForEach-Object {
            $Parameter = $_
            $ParamMandatory = $false
            $ParamSet = $null
            $ParamType = $null
            $ParamDefault = $Parameter.DefaultValue
            $ParamName = $Parameter.Name
            $Parameter.Attributes | ForEach-Object {
                if ($_.TypeName -like "Parameter" -and $_.NamedArguments -and $_.NamedArguments.ArgumentName -like "Mandatory") {
                    $ParamMandatory = if ($Parameter.Attributes.NamedArguments.Argument -like '$true') { $true }else { $false }
                }
                elseif ($_.TypeName -like "ValidateSet" -and $_.PositionalArguments) {
                    $ParamSet = $_.PositionalArguments
                }
                else {
                    $ParamType = $_.TypeName
                }
            }
            [PSCustomObject]@{
                ParamMandatory = $ParamMandatory
                ParamSet       = $ParamSet
                ParamType      = $ParamType
                ParamDefault   = $ParamDefault
                ParamName      = $ParamName
            }
        }
    }
}

TestScript.ps1

param (
    # MyInt is a number
    [Parameter(Mandatory = $true)]
    [int]$MyInt = 10,
    # MyBigInt is a big number
    [Parameter(Mandatory = $false)]
    [int64]$MyBigInt = 1GB,
    # MyString is a string
    [String]$MyString,
    # MySet is a set string
    [ValidateSet("A", "b")]
    [String]$MySet,
    # MySet is a switch
    [switch]$MySwitch
)
begin {
    Write-Host "Begin"
}
process {
    Write-Host "Process"
}
end {
    Write-Host "End"
}