What is Angular.copy

Creates a deep copy of source, which should be an object or an array.

• If no destination is supplied, a copy of the object or array is created.
• If a destination is provided, all of its elements (for arrays) or properties (for objects) are deleted and then all elements/properties from the source are copied to it.
• If source is not an object or array (inc. null and undefined), source is returned.
• If source is identical to 'destination' an exception will be thrown.

Usage

angular.copy(source, [destination]);

<div ng-controller="ExampleController">
<form novalidate class="simple-form">
Name: <input type="text" ng-model="user.name" /><br />
E-mail: <input type="email" ng-model="user.email" /><br />
Gender: <input type="radio" ng-model="user.gender" value="male" />male
<input type="radio" ng-model="user.gender" value="female" />female<br />
<button ng-click="reset()">RESET</button>
<button ng-click="update(user)">SAVE</button>
</form>
<pre>form = {{user | json}}</pre>
<pre>master = {{master | json}}</pre>
</div>

<script>
 angular.module('copyExample', [])
   .controller('ExampleController', ['$scope', function($scope) {
     $scope.master= {};

     $scope.update = function(user) {
       // Example with 1 argument
       $scope.master= angular.copy(user);
     };

     $scope.reset = function() {
       // Example with 2 arguments
       angular.copy($scope.master, $scope.user);
     };

     $scope.reset();
   }]);
</script>