Why is the event in my for loop never getting called?

Why is the event in my for loop never getting called?

I've got this function, which *is* getting called:

  1. function setReportsConfiguredForUnit(unitval) {
            $.ajax({
                type: 'GET',
                url: '@Url.Action("GetReportsConfiguredForUnit", "ReportsConfigured")',
                data: { unit: unitval },
                cache: false,
                success: function (returneddata) {
                    for (i = 0; i < returneddata.length; i++) {
                        checkConfiguredReports(returneddata[i]);
                    }
                },
                error: function () {
                    alert(returneddata.error.stringify);
                }
            }); // $.ajax({
        } // function setReportsConfiguredForUnit

...but, although data is returned (length is > 0), checkConfiguredReports() is not getting called. A 
breakpoint there:

  1. function checkConfiguredReports(rptid) {
                if (rptid === 1) {
                    $("#ckbx_produceusage").prop('checked', true);
                }
    . . .
            }

...is never reached. I tried changing the for loop from this:

  1. for (i = 0; i < returneddata.length; i++) {
                        checkConfiguredReports(returneddata[i]);
                    }

...to this:

  1. for (i = 0; i < returneddata.length; i++) {
                        checkConfiguredReports(returneddata.ReportIDsConfiguredList[i]);
                    }

...because the (CE) Controller method looks like this:

  1. public JsonResult GetReportsConfiguredForUnit(string unit)
            {
                ReportsConfiguredModel model = new ReportsConfiguredModel();
                try
                {
                    DataTable ConfiguredReportsDT = new DataTable();
                    string qry = string.Format(SQL.GetReportsConfiguredForUnitQuery, unit);
                    ConfiguredReportsDT = SQL.ExecuteSQLReturnDataTable(
                        qry,
                        CommandType.Text,
                        null
                        );

                    List<int> configuredRptIDs = ConfiguredReportsDT
                             .AsEnumerable()
                             .Select(row => row.Field<int>("ReportID"))
                             .ToList();

                    model.ReportIDsConfiguredList = configuredRptIDs;
                }
                catch (Exception ex)
                {
                    Console.WriteLine(ex.Message);
                }
                return Json(model, JsonRequestBehavior.AllowGet);
            }

...but it's still not reached. Why not?