如果！is_in_stock如何在Woocommerce上显示阻止或触发样式

Question

我试图在产品缺货时显示一个块或DIV，但条件似乎不起作用

add_action( 'woocommerce_get_availability', 'display_welcome', 10);
function display_welcome() {
global $_product;
 if ( ! $_product->is_in_stock() ) {
    ?>
         <style>
            #hello {display:block }
         </style>
<?    
     }
      }

HTML

 <div id="hello">Try this product instead</div>

Answer 1

add_action('woocommerce_get_availability', 'display_welcome', 10, 2);

function display_welcome($availability_class, $_product) {

    if ($availability_class['availability'] == 'Out of stock') {
        $availability_class['class'] = $availability_class['class'] . ' my-customclass';
        add_action('woocommerce_single_product_summary', 'hooks_add_div', 33);

        function hooks_add_div() {
            echo '<div id="helllo">mujeebu rahman</div>';
        }

    }
}