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With this custom select dropdown, I can define the WooCommerce product sale price by selecting a fixed discount rate, and stop worrying about math!
Let’s say you want to apply a 10% discount on a WooCommerce product. Its original price is $79.56. You go to the “Edit Product” page, go to the “Sale Price” input field, and enter ( $79.56 – 10% ) = $71.63. This is great as you can set the sale price, but this forces you to do some math and waste time.
What if there were a custom select dropdown, where you could directly define a fixed discount e.g. 10% or 25%, without having to calculate the final price?
Well, in today’s tutorial, we’ll see how we can display a dropdown in the Product Edit page, and at the same time how to edit the frontend price once a discount value is selected, so that you don’t need to worry about that manual sale price calculation. Enjoy!
PHP Snippet: Define Product Discount Via a Custom Dropdown @ WooCommerce Edit Product Page
/**
* @snippet Define Product Discount - WooCommerce
* @how-to Get tutoraspire.com FREE
* @author Tutor Aspire
* @compatible WooCommerce 7
* @donate $9 https://www.tutoraspire.com
*/
add_action( 'woocommerce_product_options_pricing', 'tutoraspire_set_percentage_discount' );
function tutoraspire_set_percentage_discount() {
global $product_object;
woocommerce_wp_select(
array(
'id' => '_pc_discount',
'value' => get_post_meta( $product_object->get_id(), '_pc_discount', true ),
'label' => 'Discount %',
'options' => array(
'0' => '0',
'10' => '10',
'25' => '25',
'50' => '50',
),
)
);
}
add_action( 'save_post_product', 'tutoraspire_save_percentage_discount' );
function tutoraspire_save_percentage_discount( $product_id ) {
global $typenow;
if ( 'product' === $typenow ) {
if ( defined( 'DOING_AUTOSAVE' ) && DOING_AUTOSAVE ) return;
if ( isset( $_POST['_pc_discount'] ) ) {
update_post_meta( $product_id, '_pc_discount', $_POST['_pc_discount'] );
}
}
}
add_filter( 'woocommerce_get_price_html', 'tutoraspire_alter_price_display', 9999, 2 );
function tutoraspire_alter_price_display( $price_html, $product ) {
if ( is_admin() ) return $price_html;
if ( '' === $product->get_price() ) return $price_html;
if ( get_post_meta( $product->get_id(), '_pc_discount', true ) && get_post_meta( $product->get_id(), '_pc_discount', true ) > 0 ) {
$orig_price = wc_get_price_to_display( $product );
$price_html = wc_format_sale_price( $orig_price, $orig_price * ( 100 - get_post_meta( $product->get_id(), '_pc_discount', true ) ) / 100 );
}
return $price_html;
}
add_action( 'woocommerce_before_calculate_totals', 'tutoraspire_alter_price_cart', 9999 );
function tutoraspire_alter_price_cart( $cart ) {
if ( is_admin() && ! defined( 'DOING_AJAX' ) ) return;
if ( did_action( 'woocommerce_before_calculate_totals' ) >= 2 ) return;
foreach ( $cart->get_cart() as $cart_item_key => $cart_item ) {
$product = $cart_item['data'];
if ( get_post_meta( $product->get_id(), '_pc_discount', true ) && get_post_meta( $product->get_id(), '_pc_discount', true ) > 0 ) {
$price = $product->get_price();
$cart_item['data']->set_price( $price * ( 100 - get_post_meta( $product->get_id(), '_pc_discount', true ) ) / 100 );
}
}
}