angularjs - Angular - compare many old and new values -


using angular, possible compare old , new value when changed (programmatically, or otherwise)?

i guess i'm after functionality similar ng-change can applied element , triggered whenever value in expression updated.

of course, use $scope.$watch on entire data model, find individual changed values (and injecting 'changedirection' property) feels excessive.

edit: consider data model of array of 500 objects, each 5 properties, 2 of integers need know if have increased/decreased.

you can use $watch on dot delimited paths signify individual properties in model wish watch.

<!doctype html>  <html>    <head>    <script data-require="angular.js@1.4.8" data-semver="1.4.8" src="https://code.angularjs.org/1.4.8/angular.js"></script>    <link rel="stylesheet" href="style.css" />    <script src="script.js"></script>  </head>    <body>      <div ng-controller="ctrl">      <input ng-model="model.name.first" />update:{{watchvals}}    </div>        <script>      var app = angular.module("app", []);      app.controller("ctrl", ["$scope",        function($scope) {            $scope.model = {            "name": {              "first": "john",              "last": "doe"            }          };            $scope.val = "";          $scope.$watch("model.name.first", function(newval, oldval) {            $scope.watchvals = oldval + " -> " + newval;          });        }      ]);      angular.bootstrap(document, [app.name]);    </script>  </body>    </html>


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