XmlHttpRequest.onload在边缘浏览器中不工作

XmlHttpRequest.onload . 但它确实可以在Chrome、Firefox和Safari中执行。

var xhr = new XMLHttpRequest();
xhr.responseType = "json";
xhr.open("POST", authenticateUrl, true);
xhr.setRequestHeader("X-OpenAM-Username", email);
xhr.setRequestHeader("X-OpenAM-Password", password);
xhr.setRequestHeader("Content-Type", "application/json");

alert("XHR object is created"); 

xhr.onload = function () {
  alert("start onload...");

  //...receives response from service...
}

xhr.send();

onload