Custom validation of WooCommerce checkout fields

Question

I would like add my own regular expression for validating the phone number. In my class-wc-validation.php I have changed the regular expression to my requiremen

Answer 1

You should not edit plugin files, because if you update plugin all the customization will be lost, rather you can use hook to achieve your goal. You can use using woocommerce_checkout_process hook to do this.

Here is the code:

add_action('woocommerce_checkout_process', 'wh_phoneValidateCheckoutFields');

function wh_phoneValidateCheckoutFields() {
    $billing_phone = filter_input(INPUT_POST, 'billing_phone');

    if (strlen(trim(preg_replace('/^[6789]\d{9}$/', '', $billing_phone))) > 0) {
        wc_add_notice(__('Invalid Phone Number, please check your input.'), 'error');
    }
}

Code goes in functions.php file of your active child theme (or theme). Or also in any plugin PHP files.

Please Note: By default WooCommerce use billing_phone field to take phone number, but if you have customized it then you can replace billing_phone with your field name.

Hope this helps!