Use jQuery to append multiple variables to query string
<p>I'm currently passing a variable to query string with select drop downs and jQuery using this:</p>

<pre><code>$("#filter_1").change(function(e) {
  window.location.href = '?filter_1=' + $(this).val()
});
$("#filter_2").change(function(e) {
  window.location.href = '?filter_2=' + $(this).val()
});
</code></pre>

<p>This is working great. However, if you select <code>filter_2</code> after having already passed the <code>filter_1</code> variable, <code>filter_1</code> gets overwritten in the query string. What I need now is a way to append the <code>filter_1</code> and <code>filter_2</code> and vice-a-versa. Any ideas?</p>
