<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <title>案例2</title> </head> <body> <!-- 321跳转百度 innerHtml : 可以识别标签 innerText : 直接翻译成文本 1. 获取h1标签 2. 改变 内容 每个1秒 3. 定时器 setTimeout --> <h1 id="h1" ></h1> <script> //开启定时器 返回值关闭 let count = 1; let index = setInterval(function (){ if (count == 3){ clearInterval(index) //改变地址 location.href = "https://www.baidu.com" } //业务逻辑 let h1 = document.getElementById("h1"); //h1添加内容 //h1.innerHTML = "<font color='red'>"+(4-count)+"</font>"; h1.innerText = "<font color='red'>"+(4-count)+"</font>"; //改变标识 count++; },1000); </script> </body> </html>