<!DOCTYPE html>
<html lang="en"> <head> <meta charset="UTF-8"> <title>计时器</title> <style> input { border:1px solid rgba(0,0,0,0.8); text-align: right; font-size: 20px; font-weight: bold; } </style> </head> <body> minutes: <input type="text" value="0" id="minutes"/> seconds: <input type="text" value="0" id="seconds"/> <script> var minutes = 0; var seconds = 0; var oMin = document.getElementById("minutes"); var oSec = document.getElementById("seconds"); var timer = setInterval(function(){ seconds++; if (seconds == 60) { minutes ++; seconds = 0; } if (minutes == 3) { clearInterval(timer); } oMin.value = minutes; oSec.value = seconds; },1000); </script> </body> </html>执行开始效果：
执行最终效果：
