Question

我创建了一个带有input元素和span的简单指令。使用该指令，我创建了两个带隔离范围的自定义元素。现在，我试图获得在指令的input元素中输入的数据的总和。但真的无法弄清楚如何做到这一点。这是我的控制器和指令：

angular.module('mapp',[])

.controller('ctrl',['$scope',function($scope){
    $scope.total = 0;  
}])

.directive('customElement',function(){
    return {
        restrict: 'E',
        scope:{
            data: '=info'
        },
        template: '<input type="text" ng-model="data1">\
                    <span>{{data1}}</span>'
    }
});

我希望总结所有指令元素的data1并更新$scope.total。这是HTML代码：

<div ng-app="mapp">
    <div ng-controller="ctrl">

        <custom-element info="a"></custom-element>
        <custom-element info="b"></custom-element>
        <br/>
        <br/> Total: <span>{{total}}</span>
    </div>
</div>

这是DEMO

Answer 1

Here是一个工作小提琴

angular.module('mapp', [])

    .controller('ctrl', ['$scope', function ($scope) {
    $scope.total = 0;
    $scope.a = 0;
    $scope.b = 0;
    $scope.$watchCollection('[a,b]', function () {
        console.log('watch');
        $scope.total = $scope.a + $scope.b;
    });
}])

    .directive('customElement', function () {
    return {
        restrict: 'E',
        scope: {
            data: '=info'
        },
        template: '<input type="number" ng-model="data">\
                    <span>{{data}}</span>'
    }
});

A version without $watch

A version with ng-repeat

Answer 2

Total: <span>{{a+b}}</span>这也适用于html而不使用控制器中的$watch或函数

Answer 3

您可以使用$ watch

<强>控制器

.controller('ctrl',['$scope',function($scope){
    $scope.test = {};
    $scope.test.a = 0;
    $scope.test.b = 0;
    $scope.$watch('test',function(newVal,oldVal){
        $scope.total = $scope.test.a + $scope.test.b
    },true)
    $scope.total = 0;
}])

指令将ng-model="data1"更改为ng-model="data"

template: '<input type="number" ng-model="data">\
                    <span>{{data}}</span>'

Working Fiddle

访问指令模板中的$ scope变量并更新控制器$ scope.variable

3 个答案: