Ensuring that basket page always passes to https checkout page?

Customer just commented that when they got through to our checkout page it didn't have the https prefix and, therefore, isn't secure.
How do I ensure that the basket page always passes to the https checkout page? Do I simply change this from:

<?php
//WA eCart Redirect Check Out
if (isset($_POST["LEDCart_Checkout"]) || isset($_POST["LEDCart_Checkout_x"])) {
$Redirect_redirStr="checkout.php";
if ($Redirect_redirStr != "") {
if (isset($_SERVER['QUERY_STRING']) && $_SERVER['QUERY_STRING'] != "") {
if (strpos($Redirect_redirStr, "?") < 0) {
$Redirect_redirStr .= "?".$_SERVER['QUERY_STRING'];
}
else {
$Redirect_redirStr .= "&".$_SERVER['QUERY_STRING'];
}
}

$LEDCart->redirStr = $Redirect_redirStr;
}
$LEDCart->cartAction = "Checkout";
}
?>

to...

<?php
//WA eCart Redirect Check Out
if (isset($_POST["LEDCart_Checkout"]) || isset($_POST["LEDCart_Checkout_x"])) {
$Redirect_redirStr="https:///www.ledwarehouseuk.com/checkout.php";
if ($Redirect_redirStr != "") {
if (isset($_SERVER['QUERY_STRING']) && $_SERVER['QUERY_STRING'] != "") {
if (strpos($Redirect_redirStr, "?") < 0) {
$Redirect_redirStr .= "?".$_SERVER['QUERY_STRING'];
}
else {
$Redirect_redirStr .= "&".$_SERVER['QUERY_STRING'];
}
}

$LEDCart->redirStr = $Redirect_redirStr;
}
$LEDCart->cartAction = "Checkout";
}
?>

Thank you.
NJ

That is one way to accomplish it.

another would be to use htaccess to force a https redirect or to add php coed to the page to check for https.

see the first 2 answers to this post at stack overflow for examples:
http://stackoverflow.com/questions/85816/how-can-i-force-users-to-access-my-page-over-https-instead-of-http

I only need it for the checkout page, which some users can get to outwith https, which is then insecure. It's pretty poor really.
Shouldn't this be something that is in-built into eCart?

I've looked at stackoverflow Jason but as with everything on stackoverflow there are 10 different answers and each one of those answers is usually criticised for being incorrect. :(

I've eventually gone for adding this into the .htaccess file:

RewriteEngine On
RewriteCond %{SERVER_PORT} 80
RewriteRule ^(.*)$ https://www.ledwarehouseuk.com/$1 [R,L]

This forces the https for EVERY page, which isn't what I was looking for, but I can't see any way of forcing it for just one page. Can I add the specific URL to the above, like so...

RewriteEngine On
RewriteCond %{SERVER_PORT} 80
RewriteRule ^(.*)$ https://www.ledwarehouseuk.com/checkout.php/$1 [R,L]

Thank you.
NJ

cart does not add this because not all gateway services require it.

if you use one of the remote checkout services, HTTPS is not needed.

if you look at the first response, they give a php code example that you can use on individual pages to force some pages to HTPPS:

<?php
if($_SERVER["HTTPS"] != "on")
{
    header("Location: https://" . $_SERVER["HTTP_HOST"] . $_SERVER["REQUEST_URI"]);
    exit();
}
?>