function doSendEmail (aData) {
  var sData = JSON.stringify(aData)
  $.post('dd-ajax.php', { m: 'sendEmail', sData: sData },
    function () {})
    .done(function () { console.log('Done') })
    .fail(function (err) { showMessage(`unexpected error: ${err.responseText}`) })
    .always(function () { spinner(false) })
}

if ($method == "sendEmail") {
    $sData = array_key_exists('sData', $_POST) ? $_POST['sData'] : NULL;

    foreach($sData as $line) {
        $to = $line[7];
        $name = $line[0];
        $subject = 'Email Subject';
        $message = `Dear $name, Blah blah blah`;
        mail($to, $subject, $message);
    }
}