Ajax技术应用广泛，这种异步加载技术，无需刷新网页即可更新网站内容，全局或者局部均可，所以大家应该学会这种技巧，把技术用上来。
{????"title":"Segmentfault",????"url":"https://segmentfault.com"}<!DOCTYPE html><html><head>????<meta charset="utf-8">????<title>jQuery - Ajax - Json</title>????<script src="http://code.jquery.com/jquery-3.3.1.min.js"></script>????<script>????????$(function(){????????????$("button").click(function(){????????????????$.ajax({????????????????????type:"GET",????????????????????url:"demo.json",????????????????????dataType:"json",????????????????????success:function(data){????????????????????????$("#title").text(data.title);????????????????????????$("#url").text(data.url);????????????????????}????????????????})????????????})????????})????</script></head><body>????<button name="button" type="button">加载数据</button>????<h2>title:<span id="title"></span></h2>????<h2>url:<span id="url"></span></h2></body></html>页面中需要引入jQuery库
视频教程：https://pan.baidu.com/s/1vpfT...
