How to get objects with same key values with comma separated
<p>I have an array of objects , each object have key and value .I want if object have same keys then their values shoud be comma sepated of all the values of same key.
my html code:</p>

<pre><code>&lt;p ng-repeat="item in allOptions" class="item" id="{{item.id}}"&gt;
  {{item.id}} &lt;input type="checkbox" ng-change="sync(bool, item)" ng-model="bool" &gt;  {{item}} Selected: {{bool}} 
  &lt;/p&gt;
</code></pre>

<p>and my controller code is :</p>

<pre><code> $scope.allOptions = [
    {
      "id": "1",
      "data": "one",
    },
    {
      "id": "1",
      "data": "two",
    },
    {
      "id": "2",
      "data": "three",
    },
  ];

  $scope.data = [

  ];

  $scope.sync = function(bool, item){

    if(bool){
      // add item
      $scope.data.push(item);
    } else {
      // remove item
      for(var i=0 ; i &lt; $scope.data.length; i++) {
        if($scope.data[i] == item.id){
          $scope.data.splice(i,1);
        }
      }      
    }
  };
</code></pre>

<p>In data array i have objects ,if we select same key of objects (same id value )then i want </p>

<pre><code>{
          "id": "1",
          "data": "one","two",
        }
</code></pre>