使用ng-repeat时得到未定义的恒定错误

Question

我一直在与Laravel项目合作，我想实现angular js。应当以这种方式在页面加载时调用laravel函数，并将其结果显示在下拉选项（动态下拉列表）中。但是当我重复执行ng时，它会显示“未定义常量”错误。

这是我的代码

Laravel控制器

function getproducts(){
   $data = DB::table('product as C')->select('C.*','F.name as cName','S.name as scName')->leftjoin('subcategory as S', 'S.id', '=', 'C.scId')->leftjoin('category as F', 'F.id', '=', 'S.cId')->get();

    print_r(json_encode($data));
}

视图

 <select class="form-control" ng-change="change()"><option ng-repeat="item in results ">{{item.id}}</option></select>

角度脚本

var app = angular.module('myApp', []);
  app.controller('questionCtrl',['$scope', '$http',  function($scope,$http) {
  $scope.result =[];
  $scope.getproducts = function (){
    $http.get('getproducts').then(function (response) {
       $scope.results = JSON.stringify(response.data);
     },function (error) {
       alert(error); 
    })
  }
}]);

我遇到以下错误

"Use of undefined constant item - assumed 'item' (View:purchase.blade.php)"