这种方法不存在，这似乎很奇怪。是时候加入了吗?

如果你想，你可以这样做:

var _addEventListener = EventTarget.prototype.addEventListener;
var _removeEventListener = EventTarget.prototype.removeEventListener;
EventTarget.prototype.events = {};
EventTarget.prototype.addEventListener = function(name, listener, etc) {
  var events = EventTarget.prototype.events;
  if (events[name] == null) {
    events[name] = [];
  }

  if (events[name].indexOf(listener) == -1) {
    events[name].push(listener);
  }

  _addEventListener(name, listener);
};
EventTarget.prototype.removeEventListener = function(name, listener) {
  var events = EventTarget.prototype.events;

  if (events[name] != null && events[name].indexOf(listener) != -1) {
    events[name].splice(events[name].indexOf(listener), 1);
  }

  _removeEventListener(name, listener);
};
EventTarget.prototype.hasEventListener = function(name) {
  var events = EventTarget.prototype.events;
  if (events[name] == null) {
    return false;
  }

  return events[name].length;
};

我写了3个函数来做这个:

var addEvent = function(object, type, callback)
{
    if (object != null && typeof(object) != 'undefined' && object.addEventListener)
    {
        object.isAttached = typeof object.isAttached == "undefined" ? [] : object.isAttached;
        if (!object.isAttached[type])
        {
            object.isAttached[type] = true;
            object.addEventListener(type, callback, false);
        }
    }
};

var removeEvent = function(object, type, callback)
{
    if (object != null && typeof(object) != "undefined" && typeof object.isAttached != "undefined" && object.isAttached[type])
    {
        object.removeEventListener(type, callback, false);
        object.isAttached[type] = false;
    }
};

var hasEvent = function(object, type, callback)
{
    return object != null && typeof(object) != "undefined" && typeof object.isAttached != "undefined" && object.isAttached[type];
};

函数的使用很简单:

function mousemove(e)
{
    console.log("x:" + e.clientX + ", y:" + e.clientY);
}

if (hasEvent(window, "mousemove", mousemove))
    console.log('window has "mousemove" event with "mousemove" callback');
else
    console.log('window does not have "mousemove" event with "mousemove" callback');

addEvent(window, "mousemove", mousemove);

if (hasEvent(window, "mousemove", mousemove))
    console.log('window has "mousemove" event with "mousemove" callback');
else
    console.log('window does not have "mousemove" event with "mousemove" callback');
/*
Output
window does not have "mousemove" event with "mousemove"
window has "mousemove" event with "mousemove" callback
The x and y coordinates of mouse as you move it
*/

下面是我用来检查是否存在动态附加事件侦听器的脚本。我使用jQuery附加一个事件处理程序到一个元素，然后触发该事件(在本例中是'click'事件)。通过这种方式，我可以检索和捕获仅在附加事件处理程序时才存在的事件属性。

var eventHandlerType;

$('#contentDiv').on('click', clickEventHandler).triggerHandler('click');

function clickEventHandler(e) {
    eventHandlerType = e.type;
}

if (eventHandlerType === 'click') {
    console.log('EventHandler "click" has been applied');
}

我只是写了一个脚本来让你实现这个。它为您提供了两个全局函数:hasEvent(Node elm, String事件)和getEvents(Node elm)，您可以利用它们。注意，它修改了EventTarget原型方法add/RemoveEventListener，并且不适用于通过HTML标记或elm的javascript语法添加的事件。On_event =…

更多信息在GitHub

现场演示

脚本:

var hasEvent,getEvents;!function(){function b(a,b,c){c?a.dataset.events+=","+b:a.dataset.events=a.dataset.events.replace(new RegExp(b),"")}function c(a,c){var d=EventTarget.prototype[a+"EventListener"];return function(a,e,f,g,h){this.dataset.events||(this.dataset.events="");var i=hasEvent(this,a);return c&&i||!c&&!i?(h&&h(),!1):(d.call(this,a,e,f),b(this,a,c),g&&g(),!0)}}hasEvent=function(a,b){var c=a.dataset.events;return c?new RegExp(b).test(c):!1},getEvents=function(a){return a.dataset.events.replace(/(^,+)|(,+$)/g,"").split(",").filter(function(a){return""!==a})},EventTarget.prototype.addEventListener=c("add",!0),EventTarget.prototype.removeEventListener=c("remove",!1)}();

你好，我在这里提出我的方法，它以某种方式工作，以避免在DOM的同一元素上进行多个侦听。我的方法使用JQUERY，但原理如下:

在对应用程序进行特定处理(必须在DOM元素(如click)上重新生成侦听器)之后，我们首先删除该事件以避免多次出现该事件，然后立即重新创建它。

这一原则要根据需要加以调整。这只是原理。我向你展示如何在jquery。

line 1 : $(_ELTDOM_).unbind('click');
line 2 : $(_ELTDOM_).bind('click',myFct);

我希望通过调整这个解决方案可以帮助到一些人。我坚持认为，这种解决方案不一定适用于所有情况，但它已经使解决与双、三重……相关的问题成为可能。例如，由于同一元素上的多个侦听而导致的同时处理

理论上，你可以通过addEventListener和removeEventListener来为“this”对象添加remove标志。丑八怪和我还没测试过…