woocommerce/templates/single-product/add-to-cart/variable.php

<?php
/**
 * Variable product add to cart
 *
 * @author 		WooThemes
 * @package 	WooCommerce/Templates
 * @version     2.0.3
 */

if ( ! defined( 'ABSPATH' ) ) exit; // Exit if accessed directly

global $woocommerce, $product, $post;
?>

<?php do_action('woocommerce_before_add_to_cart_form'); ?>

<form class="variations_form cart" method="post" enctype='multipart/form-data' data-product_id="<?php echo $post->ID; ?>" data-product_variations="<?php echo esc_attr( json_encode( $available_variations ) ) ?>">
	<table class="variations" cellspacing="0">
		<tbody>
			<?php $loop = 0; foreach ( $attributes as $name => $options ) : $loop++; ?>
				<tr>
					<td class="label"><label for="<?php echo sanitize_title($name); ?>"><?php echo wc_attribute_label( $name ); ?></label></td>
					<td class="value"><select id="<?php echo esc_attr( sanitize_title($name) ); ?>" name="attribute_<?php echo sanitize_title($name); ?>">
						<option value=""><?php echo __( 'Choose an option', 'woocommerce' ) ?>&hellip;</option>
						<?php
							if ( is_array( $options ) ) {

								if ( isset( $_REQUEST[ 'attribute_' . sanitize_title( $name ) ] ) ) {
									$selected_value = $_REQUEST[ 'attribute_' . sanitize_title( $name ) ];
								} elseif ( isset( $selected_attributes[ sanitize_title( $name ) ] ) ) {
									$selected_value = $selected_attributes[ sanitize_title( $name ) ];
								} else {
									$selected_value = '';
								}

								// Get terms if this is a taxonomy - ordered
								if ( taxonomy_exists( $name ) ) {

									$orderby = wc_attribute_orderby( $name );

									switch ( $orderby ) {
										case 'name' :
											$args = array( 'orderby' => 'name', 'hide_empty' => false, 'menu_order' => false );
										break;
										case 'id' :
											$args = array( 'orderby' => 'id', 'order' => 'ASC', 'menu_order' => false );
										break;
										case 'menu_order' :
											$args = array( 'menu_order' => 'ASC' );
										break;
									}

									$terms = get_terms( $name, $args );

									foreach ( $terms as $term ) {
										if ( ! in_array( $term->slug, $options ) )
											continue;

										echo '<option value="' . esc_attr( $term->slug ) . '" ' . selected( sanitize_title( $selected_value ), sanitize_title( $term->slug ), false ) . '>' . apply_filters( 'woocommerce_variation_option_name', $term->name ) . '</option>';
									}
								} else {

									foreach ( $options as $option ) {
										echo '<option value="' . esc_attr( sanitize_title( $option ) ) . '" ' . selected( sanitize_title( $selected_value ), sanitize_title( $option ), false ) . '>' . esc_html( apply_filters( 'woocommerce_variation_option_name', $option ) ) . '</option>';
									}

								}
							}
						?>
					</select> <?php
						if ( sizeof($attributes) == $loop )
							echo '<a class="reset_variations" href="#reset">' . __( 'Clear selection', 'woocommerce' ) . '</a>';
					?></td>
				</tr>
	        <?php endforeach;?>
		</tbody>
	</table>

	<?php do_action('woocommerce_before_add_to_cart_button'); ?>

	<div class="single_variation_wrap" style="display:none;">
		<div class="single_variation"></div>
		<div class="variations_button">
			<input type="hidden" name="variation_id" value="" />
			<?php woocommerce_quantity_input(); ?>
			<button type="submit" class="single_add_to_cart_button button alt"><?php echo apply_filters('single_add_to_cart_text', __( 'Add to cart', 'woocommerce' ), $product->product_type); ?></button>
		</div>
	</div>
	<div>
		<input type="hidden" name="add-to-cart" value="<?php echo $product->id; ?>" />
		<input type="hidden" name="product_id" value="<?php echo esc_attr( $post->ID ); ?>" />
	</div>

	<?php do_action('woocommerce_after_add_to_cart_button'); ?>

</form>

<?php do_action('woocommerce_after_add_to_cart_form'); ?>