CustomEvent()

The CustomEvent() constructor creates a new CustomEvent.

构造方法 CustomerEvent() 创建一个新的 CustomEvent 对象。

Syntax 语法

 event = new CustomEvent(typeArg, customEventInit);

Values 参数

typeArg

Is a DOMString representing the name of the event.

一个表示 event 名字的字符串

customEventInit可选

Is a CustomEventInit dictionary, having the following fields:  一个字典类型参数，有如下字段

• "detail", optional and defaulting to null, of type any, that is a event-dependant value associated with the event.   可选的默认值是 null 的任意类型数据，是一个与 event 相关的值
• bubbles 一个布尔值，表示该事件能否冒泡。 来自 EventInit
• cancelable 一个布尔值，表示该事件是否可以取消。 来自 EventInit

The CustomEventInit dictionary also accepts fields from the EventInit dictionary.

CustomerEventInit 字典参数同样接受来自于 Event 类构造函数的 eventInit 字典参数，如下

bubbles   一个布尔值，表示该事件能否冒泡

cancelable  一个布尔值，表示该事件是否可以取消

Example

// add an appropriate event listener
obj.addEventListener("cat", function(e) { process(e.detail) });
// create and dispatch the event
var event = new CustomEvent("cat", {
  detail: {
    hazcheeseburger: true
  }
});
obj.dispatchEvent(event);

Specifications

Browser compatibility

Polyfill

You can polyfill the CustomEvent() constructor functionality in Internet Explorer 9 and higher with the following code:

(function () {
  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;
})();

See also

• CustomEvent