php实现的ajax三级直连菜单，使用了jquery插件，但是压缩包内同样也存在prototype.js文件，看来两个伟大的Ajax库都用上了，有朋友就迷惑了，实现一个三级级联菜单，难道就这么小题大作么？其实这样用有它的理由，熟悉代码的朋友一看就会明白哦。 -Php implementation of the ajax three direct links menu, using the jquery plug-in, but the compression package also exists prototype.js file, it seems that the two great Ajax libraries are used, a friend confused, and achieve a three Cascade menu, is it such a fuss it? In fact, there is a reason to use it, familiar with the code will see a friend Oh.