问在不重新加载页面的情况下单击链接时更改url查询字符串或追加(如果不存在)

EN

function getParameterByName(name) {
      url = window.location.href;
      name = name.replace(/[\[\]]/g, "\\$&");
      var regex = new RegExp("[?&]" + name + "(=([^&#]*)|&|#|$)"),
          results = regex.exec(url);
      if (!results) return null;
      if (!results[2]) return '';
      return decodeURIComponent(results[2].replace(/\+/g, " "));
}

$('.alink').click(function(e){
   e.preventDefault();
   var _link = $(this);
   var _target = _link.attr('href').substr('1');
 var target = $('div[id="'+_target+'"]');
  $('html, body').animate({
          scrollTop: target.offset().top
        }, 500);


    var urlq = getParameterByName('tab');
    if(urlq != null){
        location.href.replace("tab="+urlq, "tab="+_target);
    } else {
        location.href+= "?tab="+_target;
    }
    console.log(urlq);
});