Show Custom Fields under "Add to Cart" button - wordpress

Question

I have using this function code to make new Custom Text Area, but have issue to show it in product page.
// Custom Field Product
add_action( 'woocommerce_product_options_general_product_data',
'woo_add_custom_general_fields' );
add_action( 'woocommerce_process_product_meta',
'woo_add_custom_general_fields_save' );
function woo_add_custom_general_fields() {
global $woocommerce, $post;
echo '<div class="options_group">';
woocommerce_wp_textarea_input(
array(
'id' => '_textarea',
'label' => __( 'Custom Text:', 'woocommerce' ),
'placeholder' => '',
'description' => __( 'Enter the custom value here.', 'woocommerce' )
)
);
echo '</div>';
}
// Save Changes to DB
function woo_add_custom_general_fields_save( $post_id ){
// Textarea
$woocommerce_textarea = $_POST['_textarea'];
if( !empty( $woocommerce_textarea ) )
update_post_meta( $post_id, '_textarea', esc_html( $woocommerce_textarea
) );
}
// Show data to product
add_action( 'woocommerce_after_add_to_cart_button',
'custom_content_after_addtocart_button', 100 );
function custom_content_after_addtocart_button() {
// custom content.
echo get_post_meta( $post->ID, '_textarea', true );
}
Looks like when press save, its storing data in DB, but its not showing in single product page. Can someone to tell me where is issue in this function?

Answer 1

The problem is that in the following function, $post is not defined. (The code was indented for clarity.)
// Show data to product
add_action( 'woocommerce_after_add_to_cart_button',
'custom_content_after_addtocart_button', 100 );
function custom_content_after_addtocart_button() {
// custom content.
echo get_post_meta( $post->ID, '_textarea', true );
}
So, a simple fix would be to add global $post; to the function:
// Show data to product
add_action( 'woocommerce_after_add_to_cart_button',
'custom_content_after_addtocart_button', 100 );
function custom_content_after_addtocart_button() {
global $post;
// custom content.
if ( $post ) {
echo get_post_meta( $post->ID, '_textarea', true );
}
}
Alternatively, you can use the global $product object:
// Show data to product
add_action( 'woocommerce_after_add_to_cart_button',
'custom_content_after_addtocart_button', 100 );
function custom_content_after_addtocart_button() {
global $product;
// custom content.
if ( $product ) {
echo get_post_meta( $product->get_id(), '_textarea', true );
}
}