Question

我已经使用$ watch在angular JS中实现了notify属性更改事件。无论什么时候更改模型，我都会得到newvalue函数中的旧值和$watch。但问题是当我加载数据初始时，我已将employee.firstname属性绑定到名为oldvalue的新属性。当我更改控件的值时，oldvalue也会发生变化。如何限制更改oldvalue属性的初始值。

angular.module('app', []);
angular.module('app').controller('ctrl', function ($scope) {
    $scope.size = 100;
    var employee = {
        "employees": [
        { "firstName": "John", "lastName": "Doe" },
        { "firstName": "Anna", "lastName": "Smith" },
        { "firstName": "Peter", "lastName": "Jones" }
        ]
    };
    $scope.employees = employee;
});

angular.module('app').directive('notifypropertychanged', function () {
    return {
        link: function (scope, el, attrs) {
            scope.$watch(attrs['notifypropertychanged'], function (newVal, oldVal) {

                var entity = attrs['entity'];
                el.css('height', newVal + 'px');
            });
        } 
    }
});

<body ng-controller="ctrl">

  <input ng-repeat="emp in employees.employees" 
    oldvalue="{{emp.firstName}}" entity="entity{{$index}}" 
    ng-model="emp.firstName" notifypropertychanged="emp.firstName" />
</body>

Angular JS在属性中保留模型的初始值

0 个答案: