Hide shipping method in the woocommerce order confirmation page - php

Question

I need to hide a shipping method depending on if a discount code is used or not.
But I don't find how to hide a shipping method in the order confirmation page.
I saw that answer but it does nothing, I tried this code to verify:
add_filter( 'woocommerce_package_rates', 'custom_shipping_rates', 100, 2 );
function custom_shipping_rates( $rates, $package ) {
exit();
}
Which should block page display but the page is well loaded.
EDIT: The filter is never called because wordpress uses stored rates in class-wc-shipping.php:
if ( ! is_array( $stored_rates ) || $package_hash !== $stored_rates['package_hash'] || 'yes' === get_option( 'woocommerce_shipping_debug_mode', 'no' ) )
{
...
// Filter the calculated rates.
$package['rates'] = apply_filters( 'woocommerce_package_rates',
$package['rates'], $package );
...
}
else
{
$package['rates'] = $stored_rates['rates'];
}

Answer 1

That code should actually work unless you have an old wc version. You can verify if that hook exist by searching for it in /plugins/woocommerce code base. If you don't find it, then something is wrong with the updates.
If you find it and your code still doesn't work, then the only other reason is that you placed that snipped of code in a point that never get fired or you simple come too late.
Could you please add where and how you placed that code so that we can see better what is going on?
Edit:
if you look above the snipped you copied you will see:
// Get rates stored in the WC session data for this package.
$wc_session_key = 'shipping_for_package_' . $package_key ;
$stored_rates = WC()->session->get( $wc_session_key );
which makes me think that is a session-related thing. So in order to fully test you need to either open the website with another browser, empty your browser cache + cookie or use an anonymous browser session

Answer 2

There's a trick to disable the usage of cache, I limited it to the "update order review" action that way:
if (preg_match('#update_order_review#i',$_SERVER['REQUEST_URI']))
{
add_filter('transient_shipping-transient-version', function($value, $name)
{
return false;
}, 10, 2);
}
add_filter( 'woocommerce_package_rates', 'custom_shipping_rates', 100, 2 );
function custom_shipping_rates( $rates, $package )
{
//get coupons
$reduc=WC()->cart->get_coupons();
$hidemr=isset($reduc['thediscountcode']);
if ($hidemr)
{
foreach($rates as $k=>$v)
{
if (preg_match('#MethodLabelToHide#i',$v->get_label()))
unset($rates[$k]);
}
}
return $rates;
}