WooCommerce Add Custom Checkout Field If Specific Product Is In Cart

Pre-Requisites

There are no pre-requisites in order for you to be able to implement this solution.

How To Implement This Solution?

Simply copy the pre-coded solution to your active theme’s functions.php or preferably the Code Snippets Plugin.

Need support with the snippet? We’re Here to Help You, Contact Us!

About This Solution

This snippet will show a custom checkout field and save the data as order meta ONLY IF a specific product is in the cart.

/**
 * Snippet Name:	WooCommerce Add Custom Checkout Field If Specific Product Is In Cart
 * Snippet Author:	ecommercehints.com
 */

// Create the custom checkout text field in the billing section of the checkout form
add_action( 'woocommerce_after_checkout_billing_form', 'ecommercehints_conditional_checkout_field' );
function ecommercehints_conditional_checkout_field($checkout) {
	if(WC()->cart->find_product_in_cart(WC()->cart->generate_cart_id(282))) {	// The Product ID to trigger the new custom field
		woocommerce_form_field( 'team_name', array(
			'type'          => 'text',
			'class'         => array('form-row-wide'),
			'required'		=> 'true',
			'label'         => 'Pub Quiz Team Name',
		), $checkout->get_value('team_name') );
	}
}

// Show an error message of field is not populated
add_action('woocommerce_checkout_process', 'ecommercehints_custom_checkout_field_validation');
function ecommercehints_custom_checkout_field_validation() {
	if(WC()->cart->find_product_in_cart(WC()->cart->generate_cart_id(282))) {	// The Product ID to trigger the new custom field
		if (empty( $_POST['team_name'] ) ) {
			wc_add_notice( 'Please enter a team name for the pub quiz.', 'error' );
		}
	}
}

// Save the custom field data as order meta
add_action( 'woocommerce_checkout_update_order_meta', 'ecommercehints_save_custom_checkout_field' );
function ecommercehints_save_custom_checkout_field( $order_id ){
	if( !empty( $_POST['team_name'] ) ) {
		update_post_meta( $order_id, 'team_name', sanitize_text_field( $_POST['team_name'] ) );
	}
}