Get Request Values from URL :
 
 
<html xmlns="http://www.w3.org/1999/xhtml"><head><script>
function gup(name) {
    name = name.replace(/[\[]/, '\\[').replace(/[\]]/, '\\]');
    var regex = new RegExp('[\\?&]' + name + '=([^&#]*)');
    var results = regex.exec(location.search);
    return results === null ? '' : decodeURIComponent(results[1].replace(/\+/g, ' '));
};
if(gup('ck')!='')
{window.location.href='http://x/default.aspx?a='+gup('a')+'&b='+gup('b')+'&c='+gup('c');
}else{window.location.href='http://x/default.aspx';};</script></head></html>