js事件

行间事件

<button onclick='functon()'></button>

js中绑定

<button id='btn'></button>
const btn = document.getElementById('btn');

绑定事件：
btn.onclick = function() {}
注销事件：
btn.onclick = null

注：相同事件会覆盖

addEventListener注册

<button id='btn'></button>

const btn = document.getElementById('btn');  
btn.addEventListener('click', function() {
})


绑定事件兼容封装:
function addEvent(domNode,eventType,handlerFunction) {
  if (window.addEventListener) {
     domNode.addEventListener(eventType,handlerFunction);
  }else {
     domNode.attachEvent(`on${eventType}`,handlerFunction);
  }
}

移除事件兼容封装:
function removeEvent(domNode,eventType,handlerFunction) {
  if (window.removeEventListener) {
     domNode.removeEventListener(eventType,handlerFunction);
  }else {
     domNode.detachEvent(`on${eventType}`,handlerFunction);
  }
}