原文地址: Javascript中点击（click）事件的3种写法
方法一：<!DOCTYPE html>
<html>
<head>
<title>Javascript中点击事件方法一</title>
</head>
<body>
<button id="btn">click</button>
<script type="text/javascript">
var btn = document.getElementById("btn");
btn.onclick = function() {
alert("hello world");
}
</script>
</body>
</html>
消除事件：btn.οnclick=null;
方法二：<!DOCTYPE html>
<html>
<head>
<title>Javascript中点击事件方法二</title>
</head>
<body>
<button id="btn">click</button>
<script type="text/javascript">
var btn = document.getElementById("btn");
btn.addEventListener('click', function() {
alert("hello wrold");
}, false)
</script>
</body>
</html>
方法三：<!DOCTYPE html>
<html>
<head>
<title>Javascript中点击事件方法三</title>
<script type="text/javascript">
function test() {
alert("hello world");
}
</script>
</head>
<body>
<button id="btn" onclick="test()">click</button>
</body>
</html>
