AngularJS学习——价格计算器

利用AngularJs实现价格计算器，总价满100免运费。(熟悉$watch的使用)

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" alt="" width="964" height="250" />

代码：

<!DOCTYPE html>
<html lang="en" ng-app="myApp">
<head>
    <meta charset="UTF-8">
    <title>价格计算器</title>
    <link rel="stylesheet" href="http://cdn.bootcss.com/bootstrap/4.0.0-alpha.2/css/bootstrap.min.css">
</head>
<body>
    <div class="container" ng-controller="MyControl">
        <h2>价格计算器</h2>
        单价：<input type="text" class="form-control" ng-model="iphone.price">
        数量：<input type="text" class="form-control" ng-model="iphone.num">
        <hr>
        <p>总价：{{ sum() | currency:'￥'}}</p>
        <p>运费：{{ iphone.yf | currency:'￥'}}</p>
        <p>合计：{{ sum() + iphone.yf | currency:'￥'}}</p>
    </div>
    <script src="http://apps.bdimg.com/libs/angular.js/1.4.6/angular.min.js"></script>
    <script>
        var myAng = angular.module('myApp',[]);
        myAng.controller('MyControl',function($scope){
            $scope.iphone = {
                price:10,
                num:1,
                yf:10
            }
            $scope.sum = function(){
                return $scope.iphone.price*$scope.iphone.num
            }
            // $watch监控对象为属性时，不加$scope
            $scope.$watch('iphone.num',function(newvalue,oldvalue){
                console.log('新值：'+ newvalue +'；旧值：'+ oldvalue)
            })
            // $watch监控对象为方法时，加$scope
            $scope.$watch($scope.sum,function(newvalue,oldvalue){
                return $scope.iphone.yf = newvalue >= 100 ? 0 : 10;
            })
        })
    </script>
</body>
</html>