<!DOCTYPE html><html><head><meta charset="utf-8"><title>W3Cschool教程(w3cschool.cn)</title></head><body><p>该实例使用 addEventListener() 方法来向按钮添加点击事件。</p><button id="myBtn">点我</button><p id="demo"></p><script>document.getElementById("myBtn").addEventListener("click", function(){document.getElementById("demo").innerHTML = "Hello World";});</script></body></html>