jquery循环请求

$(".baocun").click(function(){

        if($("#num").val()<100){

            alert("充值数量少于100");

        }else{

            

            $("#alipayment").submit();

            

            $('.zhezhao').fadeIn();

            $('#loading').fadeIn();

            

            a=setInterval(function(){

                    var _ajax=$.ajax({

                          type: "POST",

                          url: "${pageContext.request.contextPath}/app/ext/alipay/searchRecord",

                          data: null,

                          dataType: "json"

                        });

                    _ajax.done(function(data){

                        if(data.code=="0"){

                            var _text='<b>√ 成功付款</b><a href="${pageContext.request.contextPath}/app/payonline/list.jsp" class="fk">确认付款</a>';

                            $('#fk_text').html(_text);

                            clearInterval(a);

                        }

                    });

                    _ajax.fail(function(data){

                        var _text='<b>出错啦！！</b>';

                        $('#fk_text').html(_text);

                        clearInterval(a);

                    });

            },2000);

            

        }

    });