jquery如何获取json 数据的值 比如要获取 datas 数组里的 issue值

{"success":1,"datas":[{"issue":"763028","kjcode":"14","kjcodes":"2,6,6","srccode":"01,14,17,19,20,21,25,30,33,34,40,44,53,55,56,58,59,75,79,80","time":"2016-06-05 11:20:00"},{"issue":"763027","kjcode":"17","kjcodes":"8,7,2","srccode":"04,08,09,13,14,20,21,22,23,25,27,29,34,42,54,58,59,65,67,74","time":"2016-06-05 11:15:00"},{"issue":"763026","kjcode":"13","kjcodes":"5,2,6","srccode":"03,07,08,14,20,23,25,35,45,48,49,50,51,64,68,69,76,78,79,80","time":"2016-06-05 11:10:00"},{"issue":"763025","kjcode":"14","kjcodes":"3,8,3","srccode":"05,11,13,28,32,34,35,37,43,50,51,52,61,63,64,67,68,70,74,78","time":"2016-06-05 11:05:00"},{"issue":"763024","kjcode":"16","kjcodes":"0,7,9","srccode":"04,05,14,17,19,21,24,28,30,34,35,36,40,43,46,49,59,62,74,78","time":"2016-06-05 11:00:00"}]}

 var d = "{\"success\":1,\"datas\":[{\"issue\":\"763028\",\"kjcode\":\"14\",\"kjcodes\":\"2,6,6\",\"srccode\":\"01,14,17,19,20,21,25,30,33,34,40,44,53,55,56,58,59,75,79,80\",\"time\":\"2016-06-05 11:20:00\"},{\"issue\":\"763027\",\"kjcode\":\"17\",\"kjcodes\":\"8,7,2\",\"srccode\":\"04,08,09,13,14,20,21,22,23,25,27,29,34,42,54,58,59,65,67,74\",\"time\":\"2016-06-05 11:15:00\"},{\"issue\":\"763026\",\"kjcode\":\"13\",\"kjcodes\":\"5,2,6\",\"srccode\":\"03,07,08,14,20,23,25,35,45,48,49,50,51,64,68,69,76,78,79,80\",\"time\":\"2016-06-05 11:10:00\"},{\"issue\":\"763025\",\"kjcode\":\"14\",\"kjcodes\":\"3,8,3\",\"srccode\":\"05,11,13,28,32,34,35,37,43,50,51,52,61,63,64,67,68,70,74,78\",\"time\":\"2016-06-05 11:05:00\"},{\"issue\":\"763024\",\"kjcode\":\"16\",\"kjcodes\":\"0,7,9\",\"srccode\":\"04,05,14,17,19,21,24,28,30,34,35,36,40,43,46,49,59,62,74,78\",\"time\":\"2016-06-05 11:00:00\"}]}";
        d = JSON.parse(d);
        var ss = d.datas;
                for(var i in ss){
                    console.info(i);
                    console.info(ss[i].issue);
                }

 $.ajax({
                url: 'handler2.ashx',
                type: 'GET',
                dataType: 'json',
                success: function (datas) {
                    var obj = JSON.stringify(datas);
                    //$.each(obj.success, function (index, item) {
                    //    console.log(item);
                    //    alert(item);
                    //})

                    alert(obj);
                }


                                    handle2.ashx   返回的就是这些  
                                    {"success":1,"datas":[{"issue":"763028","kjcode":"14","kjcodes":"2,6,6","srccode":"01,14,17,19,20,21,25,30,33,34,40,44,53,55,56,58,59,75,79,80","time":"2016-06-05 11:20:00"},{"issue":"763027","kjcode":"17","kjcodes":"8,7,2","srccode":"04,08,09,13,14,20,21,22,23,25,27,29,34,42,54,58,59,65,67,74","time":"2016-06-05 11:15:00"},{"issue":"763026","kjcode":"13","kjcodes":"5,2,6","srccode":"03,07,08,14,20,23,25,35,45,48,49,50,51,64,68,69,76,78,79,80","time":"2016-06-05 11:10:00"},{"issue":"763025","kjcode":"14","kjcodes":"3,8,3","srccode":"05,11,13,28,32,34,35,37,43,50,51,52,61,63,64,67,68,70,74,78","time":"2016-06-05 11:05:00"},{"issue":"763024","kjcode":"16","kjcodes":"0,7,9","srccode":"04,05,14,17,19,21,24,28,30,34,35,36,40,43,46,49,59,62,74,78","time":"2016-06-05 11:00:00"}]}