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

<p>

  乘法运算：

</p>

<div ng-app='myApp' ng-controller='MathCtrl'>

    <input type="text" ng-model='leftNum'> x

    <input type="text" ng-model='rightNum'>

    =<span >{{multRes}}</span>

</div>

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

​

​

// 乘法

app.factory('MathFac', [function () {

    var factory = {};

​

    factory.mult = function(){

        var res = 1;

        for(var i = 0 ; i < arguments.length ; i++){

            res *= arguments[i];

        }

        return res;

    }   

​

    return factory;

}]);

​

app.service('CalcService', function (MathFac) {

    this.square = function(){

        return MathFac.mult.apply(null,arguments);

    }

});

​

app.controller('MathCtrl', function ($scope,CalcService) {

    $scope.leftNum = 3;

    $scope.rightNum = 5;

    $scope.multRes = 15;

​

    $scope.$watch('leftNum',function(){

        $scope.getMultRes($scope.leftNum,$scope.rightNum)

    });

    $scope.$watch('rightNum',function(){

        $scope.getMultRes($scope.leftNum,$scope.rightNum)

    });

    $scope.getMultRes = function(){

        $scope.multRes = CalcService.square.apply(null,arguments);

    }

});