EventTarget()
Baseline Widely available
This feature is well established and works across many devices and browser versions. It’s been available across browsers since July 2015.
EventTarget()
构造方法将会创建一个新的 EventTarget
对象实例。
备注:
需要显式调用这一构造函数的情况极为少见。在大多数情况下,这一函数是在继承了 EventTarget
类的构造函数中被 super
所调用的。
语法
js
new EventTarget();
参数
无。
返回值
一个 EventTarget
实例。
示例
js
class MyEventTarget extends EventTarget {
constructor(mySecret) {
super();
this._secret = mySecret;
}
get secret() {
return this._secret;
}
}
let myEventTarget = new MyEventTarget(5);
let value = myEventTarget.secret; // === 5
myEventTarget.addEventListener("foo", (e) => {
myEventTarget._secret = e.detail;
});
let event = new CustomEvent("foo", { detail: 7 });
myEventTarget.dispatchEvent(event);
let newValue = myEventTarget.secret; // === 7
规范
Specification |
---|
DOM # ref-for-dom-eventtarget-eventtarget① |
浏览器兼容性
BCD tables only load in the browser