Get custom field value but hide first 19 and last 2 characters - wordpress

Question

Geeks and code Gods,
I am having an issue with my wordpress code. I have added 3 extra columns to the dashboard's pages screen.
One of which displays the custom field 'scode'. The scode custom field holds the cart66 shortcode which adds an 'add cart' button to the page it is assigned to.
The shortcode looks like this:
[add_to_cart item="HD-NL-7010"]
Each page has a different shortcode.
Every shortcode is the same length, 31 characters long.
However Id prefer not to show the whole shortcode in the column, only the product code *HD-NL-7010* section of the code.
Is it possible to hide the first 19 and last 2 characters. Basically removing [add_to_cart item=" and "]
Below is the code I added to function.php to add the custom columns to the pages table:
function test_modify_post_table( $column ) {
$column['scode'] = 'Product Code';
$column['Price'] = 'Price';
$column['Product_Image'] = 'Image';
return $column;
}
add_filter( 'manage_pages_columns', 'test_modify_post_table' );
function test_modify_post_table_row( $column_name, $post_id ) {
$custom_fields = get_post_custom( $post_id );
switch ($column_name) {
case 'scode' :
echo $custom_fields['scode'][0];
break;
case 'Price' :
echo '£' . $custom_fields['Price'][0];
break;
case 'Product_Image' :
echo $custom_fields['Product_Image'][0];
break;
default:
}
}
add_filter( 'manage_pages_custom_column', 'test_modify_post_table_row', 10, 2 );
Thank you for reading this post. Any help would be greatly appreciated.
P.S. I'm going to ask this in another post but does anyone know how to get the Product_Image to show as an image in the page column rather than the image attachment ID?

Answer 1

I might be misunderstanding, does PHP's substr help? Something like:
case 'scode' :
echo substr( $custom_fields['scode'][0], 19, 10 );
break;
For what it's worth, I think I'd store just the code (HD-NL-7010) in the custom field, rather than the shortcode code, then apply the shortcode where needed (with do_shortcode).