Javascript中绑定click事件的四种方式介绍

<button id="vv" onclick="myfunction()" >哈哈</button>

var funcc = function () {  alert('我爱编程')  }var aa = document.getElementById('vv')aa.onclick = funcc

document.getElementById('vv').onclick = function () {  alert('hasssshhaa ')  } 

document.getElementById('vv').addEventListener('click',funcc);//或者：document.getElementById('vv').addEventListener('click',function () {  alert('hahah')  })