类似淘宝内页回到顶部代码

[{"title":"（ 5 个子文件 40KB ） 类似淘宝内页回到顶部代码","children":[{"title":"scrolltop","children":[{"title":"test.html <span style='color:#111;'> 6.39KB </span>","children":null,"spread":false},{"title":"jquery-1.3.2.min.js <span style='color:#111;'> 55.91KB </span>","children":null,"spread":false},{"title":"scrolltopcontrol.js <span style='color:#111;'> 3.74KB </span>","children":null,"spread":false},{"title":"up.png <span style='color:#111;'> 1.22KB </span>","children":null,"spread":false},{"title":"jquery.js <span style='color:#111;'> 52.81KB </span>","children":null,"spread":false}],"spread":true}],"spread":true}]