$.ajax({
                    cache: true,
                    type: "POST",
                    url: "/postcomment",
                    data: $('#pinglunform').serialize(),// 你的formid
                    async: false,
                    error: function (request) {
                        alert("Connection error");
                    },
                    success: function (data) {
                        $("#commonLayout_appcreshi").parent().html(data);
                    }
                });