js从外部函数访问ajax success（arr）

Question

此功能是一种预订功能，用户可以选择日期和设施并搜索时间。然后用户将选择时间并进行预订。我可以检查，有没有办法同时检索信用和设施价格，以便我可以从用户拥有的信用中扣除设施价格。例如，您的钱包里有50美元（信用额），设施价格为5美元，我想知道45美元（50美元至5美元）的剩余信用额度。现在，我只能设法在__deductfromwallet（arr）函数中获得信用值，并且设施价格未定义

**get the time slot selected**
$('input[type=checkbox]:checked').each(function (index) {
            var timeslotid = $(this).val();

            var url = serverURL() + "/newbooking.php";

            var JSONObject = {
                "facilities_ID": searchFacilities,
                "facilities_schedule_ID": getfacilities_schedule_ID,
                "facilities_timeslot_ID": timeslotid,
                "user_name": localStorage.getItem("userid"),
            };

            $.ajax({
                url: url,
                type: 'GET',
                data: JSONObject,
                dataType: 'json',
                contentType: "application/json; charset=utf-8",
                success: function (arr) {
                    validationMsgs("Click okay to continue ", "Booking Created", "OK" );
                    __getfaciltiesprice(arr);
                   // __getcredits(arr);
                   // __deductfromwallet(arr);

                },
                error: function () {
                    validationMsg();
                }
            });
        });
    }

 

    function __getfaciltiesprice(arr) {
**I would like to get the price of the facilities**
        var facilities_price;
        var url = serverURL() + "/getfacilities.php";
     
       
        var JSONObject = {
            "facilities_ID": searchFacilities
        };

        $.ajax({
            url: url,
            type: 'GET',
            data: JSONObject,
            dataType: 'json',
            contentType: "application/json; charset=utf-8",
            success: function (arr) {
                facilities_price = arr[0].facilities_price;
                console.log("facilities_price in _getfaciltiesprice>>" + facilities_price);
               __deductmoney(arr);
                //__getcredits(arr);
               // __deductfromwallet(arr);
             
            },
            error: function () {
                validationMsg();
            }
        });
    }
    
    function __deductmoney(arr) {
        facilities_price = arr[0].facilities_price;
        console.log("facilities_price1>>" + facilities_price);
        __getcredits(arr);
    }


    function __getcredits(arr) {
**I would like to get the credits of the user**
        var url = serverURL() + "/getprofile.php";

        var JSONObject = {
            "user_name": localStorage.getItem("userid")
        };

        $.ajax({
            url: url,
            type: 'GET',
            data: JSONObject,
            dataType: 'json',
            contentType: "application/json; charset=utf-8",
            success: function (arr) {
                var credits = arr[0].credits;
                console.log("credits1>>" + credits);
               __getcreditResults(arr);
                //__deductfromwallet(arr);
            },
            error: function () {
                validationMsg();
            }
        });
        console.log("Outside ajax credits: " + credits);
    }
   
   function __getcreditResults(arr) {
        credits = arr[0].credits;
        console.log("__getcreditResults>>" + credits);
        __deductfromwallet(arr);
    }
   

    function __deductfromwallet(arr) { 
**I would like to get the leftover credits based on the facilities price that the user get *
        facilities_price = arr[0].facilities_price;
        console.log("__deductmoney facilities price>>" + facilities_price);

        credits = arr[0].credits;
        console.log("__deductmoney credit>>" + credits);

        //var leftamt = credits - facilities_price;
        //console.log("leftamt>>" + leftamt);
    }