1.使用visibilitychange
浏览器标签页被隐藏或显示的时候会触发visibilitychange事件.
document.addEventListener("visibilitychange", function() { ???console.log(document.visibilityState); ???if(document.visibilityState == "hidden") { ???????console.log(‘隐藏‘); ???} else if (document.visibilityState == "visible") { ???????console.log(‘显示‘) ???}});2.使用onblur 和 onfocus
通过获取失去焦点判断页面是否在最前端
var count = 1;var interval_output = null; ????function output_number() { ???document.body.innerHTML += (count + " "); ???count++;} ????// window 失去焦点，停止输出window.onblur = function() { ???clearInterval(interval_output);}; ????// window 每次获得焦点window.onfocus = function() { ???// 每 1 秒在页面输出一个数 ???interval_output = setInterval(function() { ???????output_number(); ???}, 1000);}参考地址: https://zhidao.baidu.com/question/541794991.html
https://developer.mozilla.org/zh-CN/docs/Web/Events/visibilitychange
js 判断 是否在当前页面 ?当前页面是否在前端
原文地址：https://www.cnblogs.com/ooo0/p/8378729.html