[TOC] ## 一个简单的原始的回调地狱 ``` <input type="text" placeholder="你的名字"> <button>搜索</button> <h1></h1> <img src="" alt=""> <p></p> ``` ### 业务逻辑 ``` <script> $("button").click(function () { var value = $("input").val(); var baseUrl = "https://douban.uieee.com/v2/movie/" $.ajax({ url: `${baseUrl}search?q=${value}&count=1`, dataType: "jsonp", success: res => { var title = res.title; var imgUrl = res.subjects[0].images.small; var id = res.subjects[0].id; $("h1").html(title); $("img").attr("src", imgUrl) $.ajax({ url: baseUrl + id, dataType: "jsonp", success: res => { var summary = res.summary; $("p").html(summary) } }) } }) }) </script> ```