未捕获的TypeError：无法在Object.success

Question

我最近在javascript工作，我在ajax调用中遇到问题。我初始化的变量是未定义的，在这种情况下是鳕鱼。我不明白真正的问题在哪里。我正在写一段代码，我得到了错误。如果有人能提供帮助，我将不胜感激。

Cod.prototype.getAll = function (successCallback, failureCallback) {
    var service = REST_API_BASE_URL + "/cods";

    var self = this;
    $.ajax({
        url: service,
        type: "GET",
        dataType: "json",
        headers: {
            'Accept': 'application/json',
            'Content-Type': 'application/json',
            Authorization: 'Bearer ' + self.token
        },
        data: {},
        success: function (response) {
            var objsCods = [];
            var cods = response.cods;

            if (cods.length> 0){
                var numCods = cods.length;
            }


            for (var i = 0; i < numCods; ++i) {
                var objCods = new Cod();
                objCods.setID(cods[i].ID);
                objCods.setCodId(cods[i].codId);
                objCods.setLdv(cods[i].ldv);
                objCods.setAmount(cods[i].amount);
                objCods.setCustomerId(cods[i].customerId);
                objCods.setCustomerCode(cods[i].customerCode);
                objCods.setChannel(cods[i].channel);

                objsCods.push(objCods);
            }

            if (typeof successCallback === "function")
                successCallback(objsCods);
        },
        error: function (xhr, textStatus, errorThrown) {
            if (typeof failureCallback === "function") {
                var retObj = null;
                try {
                    retObj = JSON.parse(xhr.responseText);
                } catch (e) {
                    retObj = {status: {code: xhr.statusCode, message: xhr.responseText || textStatus}};
                }

                failureCallback(retObj);
            }
        }
    });
};

后端部分的一切工作正常。请帮我！提前谢谢！