title: Wordpress Custom Taxonomy Filter
body: <p>I am trying to create a product filter that works something like this:</p>
  
  <p><a href="http://www.permco.com/" rel="nofollow">http://www.permco.com/</a></p>
  
  <p>I have got it to a point that i have called in the taxonmoies and put them in drop downs.</p>
  
  <pre><code>$prodtype = array(
     'show_option_all'    =&gt; '',
     'show_option_none'   =&gt; '',
     'orderby'            =&gt; 'ID', 
     'order'              =&gt; 'ASC',
     'show_count'         =&gt; 0,
     'hide_empty'         =&gt; 1, 
     'child_of'           =&gt; 0,
     'exclude'            =&gt; '',
     'echo'               =&gt; 1,
     'selected'           =&gt; 0,
     'hierarchical'       =&gt; 0, 
     'name'               =&gt; 'cat',
     'id'                 =&gt; '',
     'class'              =&gt; 'postform',
     'depth'              =&gt; 0,
     'tab_index'          =&gt; 0,
     'taxonomy'           =&gt; 'product-types',
     'hide_if_empty'      =&gt; false,
  ); 
  $displacement = array(
     'show_option_all'    =&gt; '',
     'show_option_none'   =&gt; '',
     'orderby'            =&gt; 'ID', 
     'order'              =&gt; 'ASC',
     'show_count'         =&gt; 0,
     'hide_empty'         =&gt; 1, 
     'child_of'           =&gt; 0,
     'exclude'            =&gt; '',
     'echo'               =&gt; 1,
     'selected'           =&gt; 0,
     'hierarchical'       =&gt; 0, 
     'name'               =&gt; 'cat',
     'id'                 =&gt; '',
     'class'              =&gt; 'postform',
     'depth'              =&gt; 0,
     'tab_index'          =&gt; 0,
     'taxonomy'           =&gt; 'displacement',
     'hide_if_empty'      =&gt; false,
   ); 
  
  &lt;form&gt;
  &lt;b&gt;&lt;?php _e('Product Type'); ?&gt;&lt;/b&gt;&lt;br/&gt;
  &lt;?php wp_dropdown_categories($prodtype); ?&gt;
  &lt;br/&gt;
  &lt;script type="text/javascript"&gt;&lt;!--
  var dropdown = document.getElementById("cat");
  function onCatChange() {
      if ( dropdown.options[dropdown.selectedIndex].value &gt; 0 ) {
          location.href = "&lt;?php echo get_option('home');
  ?&gt;/?cat="+dropdown.options[dropdown.selectedIndex].value;
      }
  }
  dropdown.onchange = onCatChange;
  --&gt;&lt;/script&gt;
  &lt;b&gt;&lt;?php _e('Displacement'); ?&gt;&lt;/b&gt;&lt;br/&gt;
  &lt;?php wp_dropdown_categories($displacement); ?&gt;
  &lt;br/&gt;
  &lt;script type="text/javascript"&gt;&lt;!--
  var dropdown = document.getElementById("cat");
  function onCatChange() {
      if ( dropdown.options[dropdown.selectedIndex].value &gt; 0 ) {
          location.href = "&lt;?php echo get_option('home');
   ?&gt;/?cat="+dropdown.options[dropdown.selectedIndex].value;
      }
   }
  dropdown.onchange = onCatChange;
  --&gt;&lt;/script&gt;
  </code></pre>
  
  <p></p>
  
  <p>My issue is that I can't then get the dropdowns to refresh the page and reload the products automatically like they do on the example website. </p>
  
  <p>So what i would like it to do is once the user has selected an item from the dropdown the products refresh and load up ones matching that criteria, then when they select an option from the second dropdown i want the products to automatically filter through and show only products that match both those selections.</p>
  
  <p>Any help would be appreciated.</p>