add_to_cart_url() public method

Get the add to url used mainly in loops.
public add_to_cart_url ( ) : string
return string
$args = array('post_type' => 'product_variation', 'post_status' => array('private', 'publish'), 'numberposts' => -1, 'orderby' => 'id', 'order' => 'asc', 'post_parent' => $post->ID);
$levels = get_posts($args);
do_action('woocommerce_before_add_to_cart_button');
?>
<div class="sp-widget-levels">
	<div class="sp-widget-levels">
		<?php 
foreach ($levels as $level) {
    $level_product = new WC_Product_Simple($level->ID);
    $level_data = get_post_custom($level->ID);
    ?>
			<form id="level-<?php 
    echo $level->ID;
    ?>
-form" enctype="multipart/form-data" method="post" class="cart" action="<?php 
    echo $level_product->add_to_cart_url();
    ?>
">
				<a class="sp-widget-level" rel="<?php 
    echo $level->ID;
    ?>
">
					<div class="sp-widget-level-title">
						<?php 
    echo get_the_title($level->ID);
    ?>
						<div class="sp-level-amount">
							<strong>$<?php 
    echo isset($level_data['_price'][0]) ? $level_data['_price'][0] : 0;
    ?>
</strong>