new URL(location.href) doesn't work in IE

At the end I have fixed that by this code:

function getQueryString() {
          var key = false, res = {}, itm = null;
          // get the query string without the ?
          var qs = location.search.substring(1);
          // check for the key as an argument
          if (arguments.length > 0 && arguments[0].length > 1)
            key = arguments[0];
          // make a regex pattern to grab key/value
          var pattern = /([^&=]+)=([^&]*)/g;
          // loop the items in the query string, either
          // find a match to the argument, or build an object
          // with key/value pairs
          while (itm = pattern.exec(qs)) {
            if (key !== false && decodeURIComponent(itm[1]) === key)
              return decodeURIComponent(itm[2]);
            else if (key === false)
              res[decodeURIComponent(itm[1])] = decodeURIComponent(itm[2]);
          }

          return key === false ? res : null;
}

...

        var api = getQueryString('api');

I forgot where I found that but it is working as I needed.

IE does not support URL. You will have to add a polyfill for it.

Another solution I've been using if anyone is interested

function getParameterByName(name) {
  name = name.replace(/[\[]/, "\\[").replace(/[\]]/, "\\]");
  var regex = new RegExp("[\\?&]" + name + "=([^&#]*)"),
      results = regex.exec(location.search);
  return results === null ? "" : decodeURIComponent(results[1].replace(/\+/g, " "));
}

getParameterByName('api');