<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title>
<script>
window.onload = function () {
// 移除事件的兼容性处理
function removeEventListener(ele, eventType, fn) {
// 判断当前浏览器是否支持removeEventListener方法
if (ele.removeEventListener) {
ele.removeEventListener(eventType, fn);
} else if (ele.detachEvent) {
ele.detachEvent('on' + eventType, fn);
} else {
ele['on' + eventType] = null;
}
}
var btn = document.getElementById('btn');
function fn() {
alert('你好');
removeEventListener(btn, 'click', fn);
}
btn.addEventListener('click', fn);
}
</script>
</head>
<body>
<input type="button" value="点击" id="btn">
</body>
</html>