YUI ajax json最简单的写法
        YUI().use("node", "io", "json-parse", function(Y) {
            function handleSuccess(ioId, o) {
                console.log('-------------' + o.responseText) ;
                var inboxString = o.responseText;
                /[^}{]+?unread[^}{]+?(\d+)[^{}]+?folderId[^\d]+?2/.test(inboxString) ;
                console.log("----------------aaaaaaaa------" + RegExp.$1);
                var unreadNumNew = RegExp.$1;
               
                Y.JSON.parse(o.responseText, function(k, v) {
//                    console.log('-----------key---' + o + "-------value---" + v) ;
                });
                var unreadNum = Y.one("#folder-2 .unreadCount").get("innerHTML");
                if(unreadNum) {
                    unreadNum = unreadNum.replace(/[^0-9]/g,'');
                }
                if(unreadNumNew == unreadNum) {
                    alert('--------aaa--------');
                }
                else {
                    alert('---------bbbbb----------');
                }
            }
            function handleFailure() {
                console.log('--------------') ;
            }
            var cfg = {
                on:{
                   success:handleSuccess,
                   failure:handleFailure
                },
                method: "POST",
                data: ""
            };