<!DOCTYPE html>
<html lang="zh-CN">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0, user-scalable=0">
<meta http-equiv="X-UA-Compatible" content="ie=edge">
<title> webAPI_this关键字 </title>
<style>
.box {
width: 200px;
height: 200px;
background-color: #f00;
}
</style>
</head>
<body>
<input type="button" value="点我啊" id="btn">
<div class="box"></div>
<script>
document.getElementById('btn').onclick = function () {
console.log(this);
}
document.getElementsByClassName('box')[0].onclick = function () {
console.log(this);
};
</script>
</body>
</html>
