Compare two arrays in angular and loop over them

Question

I would like to combine two arrays on the same page to look up the right average rating for each cd, the cd list is in an ng-repeat and they can be matched both with the id_cd. How can i get the right average rating for each cd in the ng-repeat of the cd-listing?

I have the following codes in the landingpage.js

app.controller('LandingPageController',
   function LandingPageController($scope, $http) {

function GetAllCdRating() {
        $http({
            method: 'Get',
            url: "/LandingPage/GetAllCdRating"
        })
            .success(function (data) {
                $scope.AllCdRating= data;

         // the added section of Saurabh Agrawal
         $scope.getValue = function(cd){
             for (var i = 0; i < $scope.AllCdRating.length; i++) {
                 if ($scope.AllCdRating[i].id_cd == cd.id_cd) {
                 return $scope.AllCdRating[i].averageRating;
                 }
              }
          }
         })
}
GetAllCdRating();

// looks like this and holds about 200 records for now
[
 {
  "id": 1,
  "averageRating": 7,
  "id_cd": 13586
 },
 {
  "id": 2,
  "averageRating": 8,
  "id_cd": 13540
 },
 {
  "id": 3,
  "averageRating": 9,
  "id_cd": 13547
 },
 {
  "id": 4,
  "averageRating": 6,
  "id_cd": 13549
 }
]


   $scope.GetLastAddedCds = function () {
        $http({
            method: 'Get',
            url: "/LandingPage/GetLastAddedcds"
        })
            .success(function (data) {
                $scope.lastcds = data;
            })
    }
    $scope.GetLastAddedCds ();

// looks like this and holds about 5000+ records
[
 {
  "id_cd": 13586,
  "cdName": "the greatest hits",
 },
 {
  "id_cd": 13606,
  "cdName": "live or die",
 }
]
}

so far for the body section:

<div ng-controller="LandingPageController">
  <div class="srollcell" ng-repeat="cd in lastcds">
   <div>{{cd.title}}</div>
    <div>
       {{getValue(cd)}}
    </div>
  </div>
</div>

So i added your section Saurabh Agrawal (thanks) but somehow it seems it doesn't count up [i] it stays on '0'

Possible duplicate of [How to compare arrays in JavaScript?](http://stackoverflow.com/questions/7837456/how-to-compare-arrays-in-javascript) — Deepak, May 19 '17 at 11:52
Have you seen http://stackoverflow.com/questions/27030/comparing-arrays-of-objects-in-javascript ? — Vedant Terkar, May 19 '17 at 11:56
Use the console.log on the $scope.AllCdRating.length gives me 27 (what is correct for this testing dataset) but the counter still stays on 0 and does not count up. — Ewald Bos, May 19 '17 at 14:44
I did but i can't seem to combine your code with mine, i think it has to do with the time it load the data from the database, not sure tho — Ewald Bos, May 19 '17 at 15:47
I got it working with your code, had some error in the dataset. thx — Ewald Bos, May 19 '17 at 16:17

score 1 · Accepted Answer · answered May 19 '17 at 12:19

Here is the working example of what you are looking for

Try this

<!DOCTYPE html>
<html>
<head>
 <title></title>
 <script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.2.23/angular.min.js"></script>
 <script type="text/javascript">
  var myapp = angular.module('myapp', []);
  myapp.controller('FirstCtrl', function($scope) {
   $scope.myArray = [
   {
    "id": 1,
    "averageRating": 7,
    "id_cd": 13586
   },
   {
    "id": 2,
    "averageRating": 8,
    "id_cd": 13540
   },
   {
    "id": 3,
    "averageRating": 9,
    "id_cd": 13547
   },
   {
    "id": 4,
    "averageRating": 6,
    "id_cd": 13549
   }];

   $scope.myValues= [
   {
    "id_cd": 13586,
    "cdName": "the greatest hits",
   },
   {
    "id_cd": 13606,
    "cdName": "live or die",
   }];

   $scope.getValue = function(val){
    for (var i = 0; i < $scope.myArray.length; i++) {
     if ($scope.myArray[i].id_cd == val.id_cd) {
      return $scope.myArray[i].averageRating;
     }
    }
   }
  });
 </script>
</head>
<body>
 <div ng-app="myapp" ng-controller="FirstCtrl">
  <div ng-repeat="val in myValues track by $index">
   {{getValue(val)}}
  </div>
 </div>
</body>
</html>

Compare two arrays in angular and loop over them

1 Answers1