[（1）原生ajax](%EF%BC%881%EF%BC%89%E5%8E%9F%E7%94%9Fajax.md) [（2）http,get,post](%EF%BC%882%EF%BC%89http,get,post.md) [（3）跨域](%EF%BC%883%EF%BC%89%E8%B7%A8%E5%9F%9F.md) [（4）jQuery-ajax](%EF%BC%884%EF%BC%89jQuery-ajax.md) [（5）axios](%EF%BC%885%EF%BC%89aximos.md)