Functions/Test-EmailAddressValidity.ps1

<#
.SYNOPSIS
    This function verifies if an email address follows a valid pattern.
.PARAMETER emailAddress
    The email address to verify.
.EXAMPLE
    Test-EmailAddressValidity -EmailAddress "mailbox@domain.com"
#>

function Test-EmailAddressValidity {
    [CmdletBinding()]
    [OutputType([Bool])]
    param (
        # The email address to verify
        [Parameter(Mandatory=$true)]
        [ValidateNotNullOrEmpty()]
        [String]$emailAddress
    )

    # Try to cast to MailAddress type
    try {
        $null = [MailAddress]$emailAddress
        return $true
    }

    # Exception means email is not valid
    catch {
        return $false
    }
}