<!DOCTYPE html> <html> <head> <meta name="viewport" content="width=device-width" /> <title>index</title> <style> .wrapper{ width: 100%; height: 2000px; border: 1px red solid; } #content { width: 100%; overflow: hidden; } </style> </head> <body> <div class="wrapper" id="wrapper"> <div id="content"></div> </div> <script> //获取滚动条当前的位置 function getScrollTop() { var scrollTop = 0; if (document.documentElement && document.documentElement.scrollTop) { scrollTop = document.documentElement.scrollTop; } else if (document.body) { scrollTop = document.body.scrollTop; } return scrollTop; } //获取当前可视范围的高度 function getClientHeight() { var clientHeight = 0; if (document.body.clientHeight && document.documentElement.clientHeight) { clientHeight = Math.min(document.body.clientHeight, document.documentElement.clientHeight); } else { clientHeight = Math.max(document.body.clientHeight, document.documentElement.clientHeight); } return clientHeight; } //获取文档完整的高度 function getScrollHeight() { return Math.max(document.body.scrollHeight, document.documentElement.scrollHeight); } window.onscroll = function () { if (getScrollTop() + getClientHeight() == getScrollHeight()) { //ajax从这里开始 console.log("ajax从这里开始"); }} </script> </body> </html>