Php 根据所选付款方式启用禁用 WooCommerce 所需的 checkout 字段

下面将完成这项工作，添加一个隐藏字段来处理计费电话字段可见时的计费电话验证.当帐单电话字段隐藏且为空时，不会提示验证错误，允许静默下单:

// Your settings goes in here
function my_checkout_settings()
{
    return array(
        'payment_id'   => 'cheque', // The payment Id
        'field_key_id' => 'billing_phone', // The checkout field key ID
    );
}

// Add a hidden billing input field for phone validation purpose
add_action('woocommerce_billing_fields', 'add_an_hidden_billing_fields');
function add_an_hidden_billing_fields($billing_fields) {
    extract(my_checkout_settings()); // Load your settings

    // Add a hidden input field
    $billing_fields[$field_key_id . '_is_valid'] = array(
        'type' => 'hidden',
        'required' => false,
        'default' => '',
    );

    return $billing_fields;
}

// Disabling conditionnally the Billing phone validation
add_action('woocommerce_after_checkout_validation', 'disable_specific_checkout_field_validation_conditionally', 20, 2);
function disable_specific_checkout_field_validation_conditionally($data, $errors) {
    extract(my_checkout_settings()); // Load your settings

    $validation_key =  $field_key_id . '_is_valid'; // The key Id of the hidden field

    if (empty($data[$field_key_id]) && isset($data[$validation_key]) && $data[$validation_key]) {
        $errors->remove($field_key_id . '_required'); // Remove unwanted error for this field
    }
}

// Conditional Show hide billing phone checkout fields based on chosen payment methods
add_action('woocommerce_checkout_init', 'enqueue_checkout_custom_script');
function enqueue_checkout_custom_script() {
    extract(my_checkout_settings()); // Load your settings

    wc_enqueue_js("const a = 'input[name=payment_method]',
        b = a + ':checked',
        c = '#{$field_key_id}',
        d = c + '_field',
        v = c + '_is_valid',
        p = '{$payment_id}';
    
    function triggerShowHide(b, d, p, v) {
        $(b).val() !== p ? $(d).show(200) : $(d).hide(200);
        $(b).val() !== p ? $(v).val('') : $(v).val('1');
    }
    
    // On the first load
     triggerShowHide(b, d, p, v);
    
    // On payment method 'change' live event
    $('form.checkout').on('change', a, function() {
        triggerShowHide(b, d, p, v);
    });");
}

代码放在活动子主题的unctions.php文件中(或在插件中).经过测试，效果良好.