Private/Get-NpoProgramIdFromUrl.ps1

function Get-NpoProgramIdFromUrl
{
    param
    (
        [Parameter(Mandatory, ValueFromPipeline, Position = 0)]
        [string[]]$ProgramUrl
    )

    process
    {
        $ProgramUrl.ForEach{
            ($ProgramUrl -split '/')[-1]
        }
    }
}