要将事件处理程序添加到元素，请使用JavaScript addEventListener()方法。您可以尝试运行以下代码以添加事件处理程序-
<!DOCTYPE html>
<html>
<body>
<p>Click the below button.</p>
<button id = "btnid">Click me</button>
<p id = "pid"></p>
<script>
document.getElementById("btnid").addEventListener("click", displayEvent);
function displayEvent() {
document.getElementById("pid").innerHTML = Date();
}
</script>
</body>
</html>