如何将 DOM 事件作为事件处理程序绑定方法传递

Question

nav.addEventListener('mouseover',handleHover.bind(null,e,0.5))

我想将事件本身作为参数传递给绑定方法，但它给出了一个错误。 e 未定义。如何将事件本身传递给事件处理程序绑定方法？

Answer 1

您可以传递参数：

const handleHover = (event, opacity) => { 
  event.target.style.opacity = opacity; 
}

nav.addEventListener('mouseover', () => handleHover(event, 0.5));

<div id="nav">Mouse Over</div>

使用 bind（不推荐，仅作说明）：

const handleHover = () => { 
  event.target.style.opacity = opacity; 
}

nav.addEventListener('mouseover', handleHover.bind(event, opacity=0.5));

<div id="nav">Mouse Over</div>

如何将 DOM 事件作为事件处理程序绑定方法传递

How can I pass the DOM event as an event handler bind method

javascript

bind

function

event-handling

dom-events