WooCommerce B2B signup form

gistfile1.txt

// show new fields in signup form: checkbox for B2B account, billing_company & billing_vat
// perhaps the checkbox can be left away
function ca_extra_register_fields() {?>
       <p class="form-row form-row-wide">
       <?php _e( 'Ik registreer een zakelijke account', 'woocommerce' ); ?><label for="reg_billing_account"></label>
       <input type="checkbox" class="input-text" name="billing_account" id="reg_billing_account" value="<?php esc_attr_e( $_POST['billing_account'] ); ?>" />
       </p>
       <p class="form-row form-row-wide">
       <label for="reg_billing_company"><?php _e( 'Bedrijfsnaam', 'woocommerce' ); ?></label>
       <input type="text" class="input-text" name="billing_company" id="reg_billing_company" value="<?php esc_attr_e( $_POST['billing_company'] ); ?>" />
       </p>
       <p class="form-row form-row-wide">
       <label for="reg_billing_vat"><?php _e( 'BTW-nummer', 'woocommerce' ); ?></label>
       <input type="text" class="input-text" name="billing_vat" id="reg_billing_vat" value="<?php esc_attr_e( $_POST['billing_vat'] ); ?>" />
       </p>
       <div class="clear"></div>
       <?php
 }
 add_action( 'woocommerce_register_form', 'ca_extra_register_fields' );

// validate the new fields. If checkbox is checked, company & vat must be filled in
// if checkbox is removed, then vat field must be validated if company is filled in
function ca_validate_extra_register_fields( $username, $email, $validation_errors ) {

      if ( isset( $_POST['billing_account'] ) && empty( $_POST['billing_company'] ) ) {

             $validation_errors->add( 'billing_company_error', __( '<strong>Error</strong>: Indien u een zakelijke account registreert, is bedrijfsnaam een verplicht veld!', 'woocommerce' ) );
      }
 
      if ( isset( $_POST['billing_account'] ) && empty( $_POST['billing_vat'] ) ) {

             $validation_errors->add( 'billing_vat_error', __( '<strong>Error</strong>: Indien u een zakelijke account registreert, is BTW-nummer een verplicht veld!', 'woocommerce' ) );
      }

      if ( isset( $_POST['billing_company'] ) && empty( $_POST['billing_vat'] ) ) {

             $validation_errors->add( 'billing_vat_error', __( '<strong>Error</strong>: Indien u een zakelijke account registreert, is BTW-nummer een verplicht veld!', 'woocommerce' ) );
      }
         return $validation_errors;
}

add_action( 'woocommerce_register_post', 'ca_validate_extra_register_fields', 10, 3 );

// save new fields into user meta fields. using billing_ make sure the fields are stored and automatically re-used for checkout form
function ca_save_extra_register_fields( $customer_id ) {
    if ( isset( $_POST['billing_account'] ) ) {
                 // Phone input filed which is used in WooCommerce
                 update_user_meta( $customer_id, 'billing_account', sanitize_text_field( $_POST['billing_account'] ) );
          }
      if ( isset( $_POST['billing_company'] ) ) {
             //First name field which is by default
             update_user_meta( $customer_id, 'billing_company', sanitize_text_field( $_POST['billing_company'] ) );
      }
      if ( isset( $_POST['billing_vat'] ) ) {
             // Last name field which is used in WooCommerce
             update_user_meta( $customer_id, 'billing_vat', sanitize_text_field( $_POST['billing_vat'] ) );
      }
 
}
add_action( 'woocommerce_created_customer', 'ca_save_extra_register_fields' );

Thank you !