ASP.NET MVC3 AJAX.BeginForm AjaxOptions OnSuccess OnFailure问题

我的问题是调用OnFailure回调的条件是什么,运行时如何知道ajax调用失败(ajax帮助程序使用一些http响应状态代码来表示那是什么？)
而且如果updateTargetId的html更新,无论ajax调用失败或成功,那么我该如何正确地处理错误.很困惑…

解决方法

<script type="text/javascript">
        function OnSuccess() {
            alert('Success');
        }
        function OnFailure(ajaxContext) {
            var response = ajaxContext.get_response();
            var statusCode = response.get_statusCode();
            alert('Failure');
            Here you can do whatever you want with the div.
            $('#targetDiv').empty();
        }
    </script>
    <div id="targetDiv">
    @using (Ajax.BeginForm("Index","Home",new AjaxOptions 
           { 
             UpdateTargetId = "targetDiv",OnSuccess ="OnSuccess",OnFailure ="OnFailure" 
           })
      {
        ... 
      }
  </div>