woo add field to cart

field-to-cart.php

<?php 

// add_action('woocommerce_before_add_to_cart_button','wdm_add_custom_fields');
add_filter('woocommerce_add_cart_item_data','wdm_add_item_data',10,3);
add_filter('woocommerce_get_item_data','wdm_add_item_meta',10,2);
add_action( 'woocommerce_checkout_create_order_line_item', 'wdm_add_custom_order_line_item_meta',10,4 );

function wdm_add_custom_fields()
{

    global $product;

    ob_start();

    ?>
        <div class="wdm-custom-fields">
            <input type="text" name="wdm_name">
        </div>
        <div class="clear"></div>

    <?php

    $content = ob_get_contents();
    ob_end_flush();

    return $content;
}
function wdm_add_item_data($cart_item_data, $product_id, $variation_id)
{
    if(isset($_REQUEST['wdm_name']))
    {
        $cart_item_data['wdm_name'] = sanitize_text_field($_REQUEST['wdm_name']);
    }

    return $cart_item_data;
}
function wdm_add_item_meta($item_data, $cart_item)
{

    if(array_key_exists('wdm_name', $cart_item))
    {
        $custom_details = $cart_item['wdm_name'];

        $item_data[] = array(
            'key'   => 'Name',
            'value' => $custom_details
        );
    }

    return $item_data;
}
function wdm_add_custom_order_line_item_meta($item, $cart_item_key, $values, $order)
{

    if(array_key_exists('wdm_name', $values))
    {
        $item->add_meta_data('_wdm_name',$values['wdm_name']);
    }
}