Just a standard HTML form will do!
<form action="<?php echo home_url("https://wordpress.stackexchange.com/"); ?>" method="get">
<p><?php wp_dropdown_categories('taxonomy=taxonomy-1&name=taxonomy-1'); ?></p>
<p><?php wp_dropdown_categories('taxonomy=taxonomy-2&name=taxonomy-2'); ?></p>
<p><input type="submit" value="Search!" /></p>
</form>
Just replace taxonomy-1
and taxonomy-2
with the names of your taxonomies.
Important
If you registered your taxonomy with a custom query_var
, you’ll need to match it in the name
argument of wp_dropdown_categories()
.
Also, querying multiple taxonomies is not supported as of 3.02 – you’ll need the 3.1 beta, a plugin or additional filters.