Products dropdown from same category inside Woocommerce product short description

Question

In Woocommerce, I would like to add a drop down in product short description that shows all products that have the same category(ies). It will be even better if it was possible

Answer 1

2020 Update 4 - Added product_id as argument, allowing the shortcode to be used for a defined product ID (for example on a page).

The following will make a custom shortcode that you can use in your product short description (or even in the product description) and will display a dropdown from same product category than the current product.

The code:

add_shortcode( 'products_dropdown', 'wc_products_from_cat_dropdown' );
function wc_products_from_cat_dropdown( $atts ) {
        // Shortcode Attributes
        $atts = shortcode_atts( array(
            'product_id' => '', 
        ), $atts, 'products_dropdown' );
        
    $product_id = is_product() ? get_the_id() : $atts['product_id'];
    
    if ( empty($product_id) )
        return;

    ob_start();

    $query = new WP_Query( array(
        'post_type'      => 'product',
        'post_status'    => 'publish',
        'posts_per_page' => '-1',
        'post__not_in'     => array( $product_id ),
        'tax_query' => array( array(
                'taxonomy' => 'product_cat',
                'field'    => 'ids',
                'terms'    => wp_get_post_terms( $product_id, 'product_cat', array( 'fields' => 'ids' ) ) ,
        ) ),
    ) );

    if ( $query->have_posts() ) :

    echo '<div class="products-dropdown"><select name="products-select" id="products-select">
    <option value="">'.__('Choose a related product').'</option>';

    while ( $query->have_posts() ) : $query->the_post();

    echo '<option value="'.get_permalink().'">'.get_the_title().'</option>';

    endwhile;

    echo '</select> <button type="button" style="padding:2px 10px; margin-left:10px;">'._("Go").'</button></div>';

    wp_reset_postdata();

    endif;

    ?>
    <script type='text/javascript'>
        jQuery(function($){
            var a = '.products-dropdown', b = a+' button', c = a+' select', s = '';
            $(c).change(function(){
                s = $(this).val();
                console.log(s); // just for testing (to be removed)
            });
             $(b).click(function(){
                if( s != '' ) location.href = s;
            });

        });
    </script>
    <?php

    return ob_get_clean();
}

Code goes in functions.php file of your active child theme (or active theme). Tested and works.

---

USAGE

1). For single product pages: Just paste the following shortcode in the product short description (or descrition):

[products_dropdown]

2). For single product pages, inside php code:

echo do_shortcode("[products_dropdown]");

3). on any post or page within the text editor, define the product_id argument (below the defined product id is **37**):

[products_dropdown product_id="37"]

---

Answer 2

Add this to your theme's 'functions.php' which will display all products of your current product's category.

function add_products_short_description() {
    $product_cats = wp_get_post_terms( get_the_ID(), 'product_cat' );
    if ( $product_cats ) {
        $single_cat = array_shift( $product_cats );

        $product_args = array( 'post_type' => 'product', 'posts_per_page' => '-1', 'product_cat' => $single_cat->name );
        $products = new WP_Query( $product_args );
        if ( $products->have_posts() ) :  echo '<ul>';
            while ( $products->have_posts() ) : $products->the_post(); global $product; 
                echo '<li><a href="'.get_permalink( $products->ID ).'">'.get_the_title($products->ID).'</a></li>';
            endwhile;
            echo '</ul>';
        endif;
    }
}
add_action( 'woocommerce_single_product_summary', 'add_products_short_description', 15 );