Add customized column to publish listing desk

I’ve a customized publish sort referred to as E-book and I need to add the writer and e-book creator customized columns within the edit web page.

I additionally need to fetch a selected worth from every fields (I created two fields for the above columns) to show in these two further columns. I truly can show with this code under however the level is I’ve to declare variable (for instance: the $worth variable) for every information.

So might you please share me some concepts to show that with loop or somethings.

add_filter( 'manage_book_posts_columns', 'set_custom_edit_book_columns' );
add_action( 'manage_book_posts_custom_column' , 'custom_book_column', 10, 2 );

perform set_custom_edit_book_columns($columns) {
    $worth = get_field( "contact_person" );
    unset( $columns['author'] );
    $columns['book_author'] = __( 'Writer', 'your_text_domain' );
    $columns['publisher'] = __( 'Writer', 'your_text_domain' );

    return $columns;
}

perform custom_book_column( $column, $post_id ) {
    change ( $column ) {

        case 'book_author' :
            $worth = get_field( "contact_person" );
            $phrases = get_the_term_list( $post_id , '$worth' , '' , ',' , '' );
            if ( is_string( $worth ) )
                echo $worth;
            else
                _e( 'Unable to get creator(s)', 'your_text_domain' );
            break;

        case 'writer' :
            echo get_post_meta( $post_id , 'writer' , true ); 
            break;

    }
}