为什么我的参数不会传递给调度事件？

Question

好的,我已经设置了这样的事件监听器......

window.addEventListener('message', parseMessage, false);

var parseMessage = function(rawMessage) {
    console.log(rawMessage.cmd);
};

然后我就像这样触发事件:

var event = new Event('message', {'cmd':"blerg!"});

window.dispatchEvent(event);

问题是当我希望注销"blerg!"时,解析消息中的console.log正在注销未定义.

我在这里做错了什么事情,如何将'cmd'消息传递给事件？

Answer 1

1. 使用替代的用于创建自定义事件.CustomEvent Event

2. 在"详细信息"对象中指定数据(请参阅代码).

3. 我更改了事件名称,因为message它也用于postMessage API.在Chrome中运行时没有出现问题,但我不会使用它.

 

var parseMessage = function(rawMessage) {
  console.log(rawMessage);
  console.log(rawMessage.detail.cmd);
};

// changed event name
window.addEventListener('myMessage', parseMessage, false);

// data should be in a 'details' object
var evt = new CustomEvent('myMessage', {
    detail: {
      'cmd' : "blerg!"
    }
});

window.dispatchEvent(evt);

这是IE> = 9 compatibleblity(使用document.createEvent()和CustomEvent::initCustomEvent())的调整:

var evt = document.createEvent("CustomEvent");
evt.initCustomEvent('myMessage', false, false, {
    'cmd': "blerg!"
});

Answer 2

对于IE9/10 polyfill,您可以使用Mozilla提供的代码:https:
//developer.mozilla.org/en-US/docs/Web/API/CustomEvent/CustomEvent

(function () {
  if (
      typeof window.CustomEvent === "function" ||
      // In Safari, typeof CustomEvent == 'object' but it otherwise works fine
      this.CustomEvent.toString().indexOf('CustomEventConstructor')>-1
  ) { return; }

  function CustomEvent ( event, params ) {
    params = params || { bubbles: false, cancelable: false, detail: undefined };
    var evt = document.createEvent( 'CustomEvent' );
    evt.initCustomEvent( event, params.bubbles, params.cancelable, params.detail );
    return evt;
   }

  CustomEvent.prototype = window.Event.prototype;

  window.CustomEvent = CustomEvent;
})();

此处还描述了URL错误:https: //stackoverflow.com/a/22946340/1736012