Test CORS

cors-test.js

// http://www.test-cors.org/

var createCORSRequest = function(method, url) {
  var xhr = new XMLHttpRequest();
  if ("withCredentials" in xhr) {
    // Most browsers.
    xhr.open(method, url, true);
  } else {
    // CORS not supported.
    xhr = null;
  }
  return xhr;
};

var url = '';
var method = '';
var xhr = createCORSRequest(method, url);

xhr.onload = function() {
  // Success code goes here.
};

xhr.onerror = function() {
  // Error code goes here.
};

xhr.send();