WooCommerce - Show Sale Percentage Tag - put in content-product.php

woo-tags.php

function seed_show_sale_percentage() {
	global $product;
	if ( $product->is_on_sale() ) {
		if ( ! $product->is_type( 'variable' ) ) {
			$max_percentage = ( ( $product->get_regular_price() - $product->get_sale_price() ) / $product->get_regular_price() ) * 100;
		} else {
			$max_percentage = 0;
			foreach ( $product->get_children() as $child_id ) {
				$variation = wc_get_product( $child_id );
				$price = $variation->get_regular_price();
				$sale = $variation->get_sale_price();
				if ( $price != 0 && ! empty( $sale ) ) $percentage = ( $price - $sale ) / $price * 100;
				if ( $percentage > $max_percentage ) {
					$max_percentage = $percentage;
				}
			}
		}
		echo "<div class='sale-perc'><small>ส่วนลด</small>" . round($max_percentage) . "%</div>";
	}
}