自定义下拉选择显示或隐藏其他结帐的自定义字段

对于WooCommerce 3+ （更新）：

由于WooCommerce 3.0结帐字段已经改变一点点，从而不可能将字段重新排序为befo回覆。

有一个新的“优先”说法该处理场订购，用于结帐领域和我的帐户领域也是如此。

下面我只更新部分相关订货领域：

## 3. Ordering the billing fields 
// Set the order of the fields 
$billing_fields_new_order = array(
    'billing_first_name', 'billing_last_name', 'billing_email', 
    'billing_phone',  'billing_address_1', 'billing_address_2', 
    'billing_postcode', 'billing_city',  'billing_country', 
    'billing_status', 
    'billing_company', 'billing_number_id', 'billing_ser_id' 
); 
$count = 0; 
$priority = 10; 
// Updating the 'priority' argument 
foreach($billing_fields_new_order as $field_name){ 
    $count++; 
    $fields['billing'][$field_name]['priority'] = $count * $priority; 
} 
// END: returning the customized checkout fields 
return $fields; 

参考：Reordering checkout fields in WooCommerce 3

原来的答复：

这里是一个解决方案用jQu使用条件机制工作正如你所期望的... ...的PHP代码是完成了一些必要的功能...

PHP代码（进入功能。PHP）：

// Registering external jQuery/JS file 
function cfields_scripts() { 
    /* IMPORTANT NOTE: For a child theme replace get_template_directory_uri() by get_stylesheet_directory_uri() 
         The external cfields.js file goes in a subfolder "js" of your active child theme or theme.*/ 
    wp_enqueue_script('checkout_script', get_template_directory_uri().'/js/cfields.js', array('jquery'), '1.0', true); 
} 
add_action('wp_enqueue_scripts', 'cfields_scripts'); 
add_filter('woocommerce_checkout_fields', 'custom_checkout_billing_fields'); 
function custom_checkout_billing_fields($fields) { 
// 1. Creating the additional custom billing fields 
    // The "status" selector 
    $fields['billing']['billing_status']['type'] = 'select'; 
    $fields['billing']['billing_status']['class'] = array('form-row-wide, status-select'); 
    $fields['billing']['billing_status']['required'] = true; 
    $fields['billing']['billing_status']['label'] = __('User status', 'my_theme_slug'); 
    $fields['billing']['billing_status']['placeholder'] = __('Chose an option', 'my_theme_slug'); 
    $fields['billing']['billing_status']['options'] = array(
     '1' => __('Individual', ''), 
     '2' => __('Company', '') 
    ); 
    // Customizing 'billing_company' field ['required'] 
    $fields['billing']['billing_company']['required'] = false; 
    $fields['billing']['billing_company']['class'] = array('form-row-wide', 'status-group2'); 
    // The "Number ID" text field 
    $fields['billing']['billing_number_id']['type'] = 'text'; 
    $fields['billing']['billing_number_id']['class'] = array('form-row-wide'); 
    $fields['billing']['billing_number_id']['required'] = true; 
    $fields['billing']['billing_number_id']['label'] = __('Number ID', 'my_theme_slug'); 
    $fields['billing']['billing_number_id']['placeholder'] = __('Enter your Number ID', 'my_theme_slug'); 
    // The "Serial identification" text field 
    $fields['billing']['billing_ser_id']['type'] = 'text'; 
    $fields['billing']['billing_ser_id']['class'] = array('form-row-wide', 'status-group2'); 
    $fields['billing']['billing_ser_id']['required'] = false; 
    $fields['billing']['billing_ser_id']['label'] = __('Serial identification', 'my_theme_slug'); 
    $fields['billing']['billing_ser_id']['placeholder'] = __('Enter your Serial identification', 'my_theme_slug'); 
// 3. Ordering the billing fields 
    $fields_order = array(
     'billing_first_name', 'billing_last_name', 'billing_email', 
     'billing_phone',  'billing_address_1', 'billing_address_2', 
     'billing_postcode', 'billing_city',  'billing_country', 
     'billing_status', 
     'billing_company', 'billing_number_id', 'billing_ser_id' 
    ); 
    foreach($fields_order as $field) $ordered_fields[$field] = $fields['billing'][$field]; 
    $fields['billing'] = $ordered_fields; 
// Returning Checkout customized billing fields 
    return $fields; 
} 
// Process the checkout 
add_action('woocommerce_checkout_process', 'my_custom_checkout_field_process'); 
function custom_checkout_field_process() { 
    // Check if set, if its not set add an error. 
    if (! $_POST['billing_number_id']) 
     wc_add_notice(__('Please enter your Number ID.', 'my_theme_slug'), 'error'); 
    if (! $_POST['billing_ser_id']) 
     wc_add_notice(__('Please enter your Serial id.' , 'my_theme_slug'), 'error'); 
} 
// Update the order meta with field value 
add_action('woocommerce_checkout_update_order_meta', 'custom_checkout_field_update_order_meta'); 
function custom_checkout_field_update_order_meta($order_id) { 
    if (! empty($_POST['billing_number_id'])) 
     update_post_meta($order_id, 'billing_number_id', sanitize_text_field($_POST['billing_number_id'])); 
    if (! empty($_POST['billing_ser_id'])) 
     update_post_meta($order_id, 'billing_ser_id', sanitize_text_field($_POST['billing_ser_id'])); 
} 
// Display field value on the order edit page 
add_action('woocommerce_admin_order_data_after_billing_address', 'custom_checkout_field_display_admin_order_meta', 10, 1); 
function custom_checkout_field_display_admin_order_meta($order){ 
    echo '<p><span>'.__('My number ID').':</span> ' . get_post_meta($order->id, 'billing_number_id', true) . '</p>'; 
    echo '<p><span>'.__('My serial identification').':</span> ' . get_post_meta($order->id, 'billing_ser_id', true) . '</p>'; 
} 

的Javascript cfields.js代码（外部文件）：

// This file named "cfields.js" goes in a subfolder "js" of your active child theme or theme 
jQuery(document).ready(function($){ 
    $('#billing_company_field').hide(function(){ 
     $(this).removeClass("validate-required"); 
    }); 
    $('#billing_ser_id_field').hide(function(){ 
     $(this).removeClass("validate-required"); 
    }); 
    $("#billing_number_id_field").addClass("validate-required"); 
    $("#billing_status").change(function(){ 
     if($("#billing_status option:selected").val() == "2"){ 
      $('#billing_company_field').show(function(){ 
       $(this).addClass("validate-required"); 
      }); 
      $('#billing_ser_id_field').show(function(){ 
       $(this).addClass("validate-required"); 
      }); 
     } else if($("#billing_status option:selected").val() == "1"){ 
      $('#billing_company_field').hide(function(){ 
       $(this).removeClass("validate-required"); 
      }); 
      $('#billing_ser_id_field').hide(function(){ 
       $(this).removeClass("validate-required"); 
      }); 
     } 
    }); 
}); 

所有这些代码已经被测试和工程