Get userinput and validate it

Get-UserInput.ps1

function Get-UserInput {
    <#
    .SYNOPSIS
        Asks for user input, then validates response.
    
    .DESCRIPTION
        Asks for user input, then validates response.
    
    .PARAMETER Prompt
        The message to show to the user as input prompt.
    
    .PARAMETER ErrorMessage
        A customized error message to show.
        Used with ValidatePattern and ValidateScript.
        Uses the format operator - use "{0}" inside the string (without quotes) to reference the user input.
    
    .PARAMETER ValidatePattern
        A regex pattern the user input must match.
    
    .PARAMETER ValidateSet
        A list of legal values the user may provide.
    
    .PARAMETER ValidateScript
        A scriptblock that must return $true in order to validate user input.
        Within the scriptblock, $args[0] is the user input.
    
    .PARAMETER Terminate
        Whether the input prompt should terminate with a terminating exception if the user provides an invalid answer.
    
    .EXAMPLE
        PS C:\> Get-UserInput -Prompt "User: " -ValidatePattern '^\S+$' -ErrorMessage "Input may not contain a whitespace. Value provided: {0}"

        Asks for user input, ensuring no whitespace was offered.
    #>
    [CmdletBinding()]
    param (
        [string]
        $Prompt = " ",

        [string]
        $ErrorMessage,

        [string]
        $ValidatePattern,

        [string[]]
        $ValidateSet,

        [ScriptBlock]
        $ValidateScript,

        [switch]
        $Terminate
    )

    while ($true) {
        $answer = Read-Host -Prompt $Prompt

        #region Validate Pattern
        if ($ValidatePattern -and $answer -notmatch $ValidatePattern) {
            if ($ErrorMessage) {
                Write-Warning ($ErrorMessage -f $answer)
                if ($Terminate) { throw ($ErrorMessage -f $answer) }
            }
            else {
                Write-Warning "Invalid input: $answer does not match $ValidatePattern"
                if ($Terminate) { throw "Invalid input: $answer does not match $ValidatePattern" }
            }
            continue
        }
        #endregion Validate Pattern

        #region Validate Set
        if ($ValidateSet -and $answer -notin $ValidateSet) {
            Write-Warning "Invalid input: $answer is not one of $($ValidateSet -join ",")"
            if ($Terminate) { throw "Invalid input: $answer is not one of $($ValidateSet -join ",")" }
            continue
        }
        #endregion Validate Set

        #region Validate Script
        try { $testResult = & $ValidateScript $answer }
        catch {
            Write-Warning "Error testing answer: $_"
            if ($Terminate) { throw }
            continue
        }
        if (-not $testResult) {
            $message = "Error validating $answer - test script did not return true: $ValidateScript"
            if ($ErrorMessage) { $message = $ErrorMessage -f $answer }
            Write-Warning $message
            if ($Terminate) { throw $message }
            continue
        }
        #endregion Validate Script

        return $answer
    }
}