Hide shipping method by product id or category - Exclude a shipping method if the cart contains certain products or product categories. https://www.damiencarbery.com/2022/10/hide-shipping-method-by-product-id-or-category

hide-shipping-method-id-category.php

<?php
/*
Plugin Name: Hide shipping method by product id or category
Plugin URI: https://www.damiencarbery.com/2022/10/hide-shipping-method-by-product-id-or-category
Description: Exclude a shipping method if the cart contains certain products or product categories.
Author: Damien Carbery
Version: 0.1
*/

// Filter shipping methods in the checkout - do not show An Post if a Craft item is in the cart.
add_filter( 'woocommerce_package_rates', 'dcwd_filter_shipping_methods', 10, 2 );
function dcwd_filter_shipping_methods( $rates, $package ) {
	$method_name = 'An Post';  // This can be a partial or full name.
	// If the product is one of the following then exclude the shipping method.
	$products_not_excluded_method = array(
		13083,  // https://craftyletters.ie/product/smoothing-acrylic-round-discs-varied-sizes/
	);
	// Go through the cart again looking for category matches.
	$categories_not_excluded_method = array(
		'crafts',  // Crafts
		'personalised-gifts', // Personalised Gifts
		'hoops-inserts', // Hooks & Inserts
	);
	
	// No configuration needed beyond this point.

	$shipping_method_key = false;

	// Find shipping method ID.
	foreach ( $rates as $rate_key => $rate ) {
        //error_log( 'Rate label: ' . $rate->get_label() );

		if ( is_object( $rate ) && method_exists( $rate, 'get_label' ) && false !== strpos( $rate->get_label(), $method_name ) )  {
			$shipping_method_key = $rate_key;
		}
	}

	// Go through all products and check the product ID and category
	if ( $shipping_method_key !== false ) {
		$exclude_shipping_option = false;

		foreach ( $package['contents'] as $key => $item ) {
			if ( in_array( $item['product_id'], $products_not_excluded_method ) ) {
				$exclude_shipping_option = true;
				break;
			}
		}

		foreach ( $package['contents'] as $key => $item ) {
			$categories = get_the_terms( $item['product_id'], 'product_cat' );

			if ( $categories && ! is_wp_error( $categories ) && is_array( $categories ) ) {
				foreach ( $categories as $category ) {
					//error_log( 'Category: ' . $category->slug );
					if ( in_array( $category->slug, $categories_not_excluded_method ) ) {
						$exclude_shipping_option = true;
						break;
					}
				}
			}
		}

		// Craft item has been found, disable the shipping method.
		if ( $exclude_shipping_option === true ) {
			unset( $rates[$shipping_method_key] );
		}
	}

	return $rates;
}