Limit taxonomy terms added to a custom post type

I've created a Custom Post Type and a Custom Taxonomy.

In WP Admin, how can I limit amount of taxonomy terms that are added to the custom post type? I want to add no more than one tag into the post. After adding one tag, adding more should be disabled or a message should appear.

Any help appreciated much.

I've created a Custom Post Type and a Custom Taxonomy.

In WP Admin, how can I limit amount of taxonomy terms that are added to the custom post type? I want to add no more than one tag into the post. After adding one tag, adding more should be disabled or a message should appear.

Any help appreciated much.

• custom-post-types
• custom-taxonomy
• limit

Share Improve this question asked Nov 7, 2014 at 12:34 SLHSLH 1,4521414 silver badges2222 bronze badges

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2 Answers 2

Sorted by: Reset to default 0

You can do it with jQuery with easyly. Count your tags and limit it!

1. C = Re item's number
2. L = Your limit number
3. if ( C==L ) add class "disable" to div

$(document).ready(function(){
    var L = 10;
    var $items = $('#post_tag .tagchecklist span');
    if($items.length == L){
        $("#post_tag").addClass("disable"); // or alert("ok")
    }
});

To limit the number of taxonomy terms that can be added to a custom post type in WordPress, you can use a combination of JS and WP

    function limit_taxonomy_terms($taxonomy, $post_type, $limit = 1) {
    // JavaScript for Admin Interface
    add_action('admin_footer', function() use ($taxonomy, $post_type, $limit) {
        global $pagenow;

        // Check if we are on the edit page of the specified post type
        if ($pagenow === 'post.php' && isset($_GET['post']) && get_post_type($_GET['post']) === $post_type) {
            ?>
            <script type="text/javascript">
                jQuery(document).ready(function($) {
                    // Check when a term is added to the taxonomy
                    $(document).on('change', '#<?php echo $taxonomy; ?>', function() {
                        var termCount = $(this).find('option:selected').length;
                        // If the maximum limit is reached, disable input field or display a message
                        if (termCount >= <?php echo $limit; ?>) {
                            // Disable input field or display a message
                            // For example:
                            // $(this).prop('disabled', true);
                            // or
                             alert('You can only add <?php echo $limit; ?> term(s).');
                        }
                    });
                });
            </script>
            <?php
        }
    });


    // Backend validation to restrict terms assignment

    add_action('save_post', function($post_id) use ($taxonomy, $limit) {
        $terms = wp_get_post_terms($post_id, $taxonomy);
        $term_count = count($terms);
        // If the number of assigned terms exceeds the limit, display an error message
        if ($term_count > $limit) {
            wp_die(sprintf(__('You can only assign %d term(s) to this post.'), $limit));
        }
    }, 10, 1);
}

// Usage example: Limit 'category' taxonomy terms for 'post' post type to 2 terms

limit_taxonomy_terms('category', 'post', 2);