新增額外庫存狀態選項

// 新增庫存狀態選項
function filter_woocommerce_product_stock_status_options( $status ) {
  // Add new statuses
  $status['pre_order'] = __( 'Pre order', 'woocommerce' );
  $status['contact_us'] = __( 'Contact us', 'woocommerce' );

  return $status;
}
add_filter( 'woocommerce_product_stock_status_options', 'filter_woocommerce_product_stock_status_options', 10, 1 );

// Availability text
function filter_woocommerce_get_availability_text( $availability, $product ) {
  switch( $product->get_stock_status() ) {
    case 'pre_order':
      $availability = __( 'Pre order', 'woocommerce' );
    break;
    case 'contact_us':
      $availability = __( 'Contact us', 'woocommerce' ); 
    break;
  }

  return $availability; 
}
add_filter( 'woocommerce_get_availability_text', 'filter_woocommerce_get_availability_text', 10, 2 );

// Availability class
function filter_woocommerce_get_availability_class( $class, $product ) {
  switch( $product->get_stock_status() ) {
    case 'pre_order':
      $class = 'pre-order'; 
    break;
    case 'contact_us':
      $class = 'contact-us'; 
    break;
  }

  return $class;
}
add_filter( 'woocommerce_get_availability_class', 'filter_woocommerce_get_availability_class', 10, 2 );