Question

如果我使用ng-option，我可以从select值得到一个对象，但是，如果我在选项指令上使用ng-repeat，我只能得到字符串。我试图用angular.fromJson（）将字符串从ng-repeat转换为对象但是我失败了：我的代码是：

<!DOCTYPE html>
<html>
<script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.6.4/angular.min.js"></script>
<body>

<div ng-app="myApp" ng-controller="myCtrl">

<p>Select a car:</p>

<select ng-model="selectedCar">
<option ng-repeat="(x, y) in cars" value="{{y}}">{{y.brand}}</option>
</select>

<input type="text" value="{{selectedCar}}">
<h1>You selected: {{selectedCarObj.brand}}</h1>
<h2>Model: {{selectedCarObj.model}}</h2>
<h3>Color: {{selectedCarObj.color}}</h3>

<h1>You selected: {{selectedCar}}</h1>
<h2>Model: {{selectedCar}}</h2>
<h3>Color: {{selectedCar}}</h3>

<p>The visible text inside the dropdown list can also be a property of the value object.</p>

</div>

<script>
var app = angular.module('myApp', []);
app.controller('myCtrl', function($scope) {
    $scope.cars = {
        car01 : {brand : "Ford", model : "Mustang", color : "red"},
        car02 : {brand : "Fiat", model : "500", color : "white"},
        car03 : {brand : "Volvo", model : "XC90", color : "black"}
    }
    $scope.selectedCarObj = angular.fromJson($scope.selectedCar);
});
</script>

</body>
</html>

如果我换行：

$scope.selectedCarObj = angular.fromJson($scope.selectedCar);

要：

$scope.selectedCarObj = angular.fromJson({brand : "Ford", model : "Mustang", color : "red"});

它正在运作！

为什么我无法获得{{selectedCarObj.brand}}值？

在选择lis上，选项值为：

<option ng-repeat="(x, y) in cars" value="{"brand":";Fiat";,";model":"500","color":"white"}" class="ng-binding ng-scope">Fiat</option><!-- end ngRepeat: (x, y) in cars -->

有人可以帮我理解为什么它不起作用吗？

也许html caharacters？！？

非常感谢。

Answer 1

您缺少ng-change：

var app = angular.module('myApp', []);
app.controller('myCtrl', function($scope) {
    $scope.cars = {
        car01 : {brand : "Ford", model : "Mustang", color : "red"},
        car02 : {brand : "Fiat", model : "500", color : "white"},
        car03 : {brand : "Volvo", model : "XC90", color : "black"}
    }
    $scope.GetObject = function(){
    $scope.selectedCarObj = angular.fromJson($scope.selectedCar);
    
}
});

<html>
<script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.6.4/angular.min.js"></script>
<body>

<div ng-app="myApp" ng-controller="myCtrl">

<p>Select a car:</p>

<select ng-model="selectedCar" ng-change="GetObject()">
<option ng-repeat="(x, y) in cars" value="{{y}}">{{y.brand}}</option>
</select>

<input type="text" value="{{selectedCar}}">
<h3>Json: {{selectedCar}}</h3>
object is :
<h3>brand: {{selectedCarObj.brand}}</h3>
<h3>model: {{selectedCarObj.model}}</h3>
<h3>color: {{selectedCarObj.color}}</h3>

<p>The visible text inside the dropdown list can also be a property of the value object.</p>

</div>
</body>
</html>

Answer 2

另一种替代解决方案是创建自定义过滤器以将字符串转换为对象并返回相关属性

app.filter('jsonFilt',function(){
  return function(item,name){
     if(item){
       item = JSON.parse(item);
       return item[name];
     } 
  }
});

像html一样调用html中的过滤器

<input type="text" value="{{selectedCar}}">
<h1>You selected: {{selectedCar | jsonFilt : 'brand'}}</h1>
<h2>Model: {{selectedCar | jsonFilt : 'model'}}</h2>
<h3>Color: {{selectedCar | jsonFilt : 'color'}}</h3>

演示

＆＃13;

var app = angular.module('myApp', []);
app.controller('myCtrl', function($scope) {
    $scope.cars = {
        car01 : {brand : "Ford", model : "Mustang", color : "red"},
        car02 : {brand : "Fiat", model : "500", color : "white"},
        car03 : {brand : "Volvo", model : "XC90", color : "black"}
    }
    $scope.selectedCarObj = angular.fromJson($scope.selectedCar);
});
app.filter('jsonFilt',function(){
  return function(item,name){
     if(item){
       item = JSON.parse(item);
       return item[name];
     } 
  }
});

＆＃13;

<script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.2.23/angular.min.js"></script>
<div ng-app="myApp" ng-controller="myCtrl">

<p>Select a car:</p>

<select ng-model="selectedCar">
<option ng-repeat="(x, y) in cars" value="{{y}}">{{y.brand}}</option>
</select>

<input type="text" value="{{selectedCar}}">
<h1>You selected: {{selectedCar | jsonFilt : 'brand'}}</h1>
<h2>Model: {{selectedCar | jsonFilt : 'model'}}</h2>
<h3>Color: {{selectedCar | jsonFilt : 'color'}}</h3>

<h1>You selected: {{selectedCar}}</h1>
<h2>Model: {{selectedCar}}</h2>
<h3>Color: {{selectedCar}}</h3>

<p>The visible text inside the dropdown list can also be a property of the value object.</p>

</div>

＆＃13;

如何使用angular.fromJson（）从ng-repeat获取对象

2 个答案: