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<div class="container" data-ng-app="">
    <div ng-controller="parentCtrl">
        <h1>부모 이름 : {{parent.name}}</h1>
        <div ng-controller="childCtrl" style="padding-left: 20px;">
            <h2>부모이름 : {{parent.name}}</h2>
            <h2>자식이름 : {{child.name}}</h2>
            <button type="button" class="btn btn-default" ng-click="changeParentName()">부모이름변경</button>
        </div>
    </div>
</div>

var parentCtrl = function($scope){
    $scope.parent = {name: "parent Kim"};
};

var childCtrl = function($scope){
    $scope.child = {name: "child Ko"};
    $scope.changeParentName = function(){
        $scope.parent.name = "another Kim";
    };
};