<script src="https://cdn.staticfile.org/angular.js/1.6.6/angular.min.js"></script>

<div ng-app="myApp">

    <p ng-controller="ctr1">

        {{firstName}}

        <button ng-click="btn()">

            点我

        </button>

    </p>

    <p ng-controller="ctr2">

        {{secondName}}

        <button ng-click="btn()">

            点我

        </button>

    </p>

    <div ng-controller="ctr5">

        <ul>

            <li ng-repeat="x in names">

                {{firstName}}==={{x}}==={{secondName}}

                <button ng-click="btn()">

                    点我

                </button>

            </li>

        </ul>

    </div>

</div>

var app = angular.module("myApp", []);

app.controller("ctr1",

function($scope, $rootScope) {

    $scope.firstName = "AAA";

    $rootScope.secondName = "BBB";

    $scope.btn = function() {

        alert($scope.firstName + " " + $rootScope.firstName + "===" + $scope.secondName + " " + $rootScope.secondName);

    }

});

app.controller("ctr2",

function($scope, $rootScope) {

    $scope.secondName = "CCC";

    $rootScope.firstName = "DDD";

    $scope.btn = function() {

        alert($scope.firstName + " " + $rootScope.firstName + "===" + $scope.secondName + " " + $rootScope.secondName);

    }

});

app.controller("ctr5",

function($scope, $rootScope) {

    $scope.names = ["111", "222", "333"];

    $scope.btn = function() {

        alert($scope.firstName + " " + $rootScope.firstName + "===" + $scope.secondName + " " + $rootScope.secondName);

    }

});