<div id="ajax_search">    @using (Ajax.BeginForm(        "Search",//Action        "Test",//Controller        new AjaxOptions        {            InsertionMode = InsertionMode.InsertAfter,            HttpMethod = "GET",            UpdateTargetId = "ajax_search",            LoadingElementId = "loader",//服务端在执行操作时，展示一个进度给用户看，相当于进度条            OnFailure = "Failed",//服务端执行失败后调用的js方法            OnSuccess = "Success"//服务端执行成功后调用的js方法        }))    {        <input type="text" name="q" />        <input type="submit" value="http://www.mamicode.com/搜索" />        <img id="loader" style="display: none" src="http://www.mamicode.com/~/Content/img/progress.gif" />    }</div>

//异步搜索        public ActionResult Search(string q)        {           // throw new Exception("故意让你报错");           // System.Threading.Thread.Sleep(3000);            string msg = "你搜索的关键词："+q;            return PartialView("_search", msg);        }