javascript - Select2 onchange select option then append or strip url depending on option -

currently have select dropdown filter setup via php this:

<?php if($this->config->get("config_show_tmall_only")){?>   <?php if(isset($code) && $code=="tmall"){?>   <select id="tmallfilter">     <option value="&code=tmall">tmall only</option>     <option value="">taobao &amp; tmall</option>   </select>   <?php }else{?>   <select id="tmallfilter">     <option value="">taobao &amp; tmall</option>     <option value="&code=tmall">tmall only</option>   </select>   <?php }?> <?php }?> 

it detects if &code=tmall in url , runs first block

i appending &code=tmall through script runs how need

$('#tmallfilter').bind('change', function () {     var brwsr_url=document.url;     var redirecturl= brwsr_url + $(this).val();     location.href = redirecturl; }); 

the problem running when need go taobao & tmall can add url, not strip characters based on select.

is there way can strip &code=tmall url when select taobao & tmall option?

this strip away &code=tmall using string.replace:

$('#tmallfilter').bind('change', function () {     var brwsr_url = document.url;     var redirecturl= brwsr_url.replace(/&code=tmall/, '') + $(this).val();     location.href = redirecturl; });