javascript - Angularjs 根据 id 过滤嵌套 JSON 数据

Question

我检查了这个笨蛋: 笨蛋:http://plnkr.co/edit/5E7FYqNNqDuqFBlyDqRh?p=preview

这在某种程度上对我有用。但我的问题是我有一个嵌套的 json 数据。上述过滤器代码不起作用的地方。以下是我的 json 数据，我根据“category_id”键进行过滤。

JSON::

[{
"category_id": 5,
"category_name": "Home",
"image": "Home_544f75960ee0e",
"parent_id": 0,
"i": 1,
"categories": [
  {
    "category_id": 7,
    "category_name": "Home Safe",
    "image": "Home Safe_5411af45ac923",
    "parent_id": 5,
    "i": 2,
    "categories": [
      {
        "category_id": 13,
        "category_name": "Mechanical Safes ",
        "image": "Mechanical Safes _540ab92ee1ff7",
        "parent_id": 7,
        "i": 3
      },
      {
        "category_id": 14,
        "category_name": "Electronic Safes ",
        "image": "Electronic Safes _540ab93c6e305",
        "parent_id": 7,
        "i": 4
      }
    ]
  },
  {
    "category_id": 8,
    "category_name": "Video Door Phones ",
    "image": "Video Door Phones _540ab57a466ff",
    "parent_id": 5,
    "i": 3
  },
  {
    "category_id": 9,
    "category_name": "Alarm Systems ",
    "image": "Alarm Systems _540ab58b903e9",
    "parent_id": 5,
    "i": 4
  },
  {
    "category_id": 10,
    "category_name": "Home CCTV Cameras ",
    "image": "Home CCTV Cameras _540ab59c59f44",
    "parent_id": 5,
    "i": 5
  },
  {
    "category_id": 11,
    "category_name": "Car Safes ",
    "image": "Car Safes _540ab5b0dcc57",
    "parent_id": 5,
    "i": 6
  },
  {
    "category_id": 12,
    "category_name": "Hotel Safes ",
    "image": "Hotel Safes _540ab5bddae51",
    "parent_id": 5,
    "i": 7
  }
]},{
"category_id": 6,
"category_name": "Institution",
"image": "Institution_541304aa0a52d",
"parent_id": 0,
"i": 2,
"categories": [
  {
    "category_id": 15,
    "category_name": "Physical Security Products ",
    "image": "Physical Security Products _54130515e2cb3",
    "parent_id": 6,
    "i": 3,
    "categories": [
      {
        "category_id": 18,
        "category_name": "Record Protecting Equipment ",
        "image": "Record Protecting Equipment _541305cb5f47a",
        "parent_id": 15,
        "i": 4
      },
      {
        "category_id": 19,
        "category_name": "Burglary and Fire Resistant Safes",
        "image": "Burglary and Fire Resistant Safes_541305db69acf",
        "parent_id": 15,
        "i": 5
      },
      {
        "category_id": 20,
        "category_name": "Vault Equipment ",
        "image": "Vault Equipment _541305e8d905c",
        "parent_id": 15,
        "i": 6
      },
      {
        "category_id": 21,
        "category_name": "Vault Accessories",
        "image": "Vault Accessories_541305f6ed3a4",
        "parent_id": 15,
        "i": 7
      }
    ]
  },
  {
    "category_id": 16,
    "category_name": "Premises Security Solutions ",
    "image": "Premises Security Solutions _54130525074c9",
    "parent_id": 6,
    "i": 4
  },
  {
    "category_id": 17,
    "category_name": "Marine Solutions ",
    "image": "Marine Solutions _54130530a10da",
    "parent_id": 6,
    "i": 5
  }
]}]

这里我可以过滤“category_id”= 5，但无法过滤“category_id”= 7

@josep 以下是我的代码:

var categoriesdata = $filter('filter')($rootScope.catjsondata, {category_id:$stateParams.categoryId})[0];

此处 $rootscope.catjsondata 包含嵌套的 json 数据。 $stateparams.categoryId 将为我提供在列表中单击的对象的category_id。所以每次id都会改变。它不是硬编码的。这些值是动态的。

以下是我的 Controller 代码:

.controller('SubCategoriesCtrl', function($scope, $filter, $stateParams, $ionicNavBarDelegate, subcategoriesfactory, globalurlfactory, $rootScope) {
$scope.baseUrl = globalurlfactory;
console.log("$rootScope.catjsondata :: ", $rootScope.catjsondata);
console.log("$stateParams.categoryId :: ", $stateParams.categoryId);    

var categoriesdata = $filter('filter')($rootScope.catjsondata, {category_id:$stateParams.categoryId})[0];

console.log("categoriesdata ::::: ", categoriesdata);
    //$rootScope.catjsondata = categoriesdata;
    $scope.categoryTitle = categoriesdata.category_name;
    $scope.categoriesIn = categoriesdata.cats_in;
    $scope.categories = categoriesdata.categories;
    $scope.has_product = categoriesdata.has_product;

    if(categoriesdata.has_product == "yes")
    {
        $scope.categoryTitle = categoriesdata.category_name;
        $scope.products = categoriesdata.product;
    }


$scope.goBack = function(){
    $scope.isBack = true;
    $ionicNavBarDelegate.back();
}})

Answer 1

正如其他人提到的，由于没有对此的内置支持(据我所知)并且您不知道树的深度，因此您必须递归地(或迭代地，递归地更简单)找到它。 这是一个更新的 plunker: http://plnkr.co/edit/sFaBnCnhXzx08pVX5qXe?p=preview

另外还附上了关键函数(只是一个简单的递归，通过表达式查找元素):

.filter('recursiveExpression', function($filter) {
    return function(input, exp) {
        return recursivelyFilterExpression(input, exp);
    }

    function recursivelyFilterExpression(input, exp) {
        var filterResult = $filter('filter')(input, exp);
        // Any result?
        if (filterResult.length > 0) {
            return filterResult[0];
        }

        if (angular.isArray(input) || angular.isObject(input)) {
            for (var key in input) {
                if (angular.isArray(input[key]) || angular.isObject(input[key])) {
                    var internalResult = recursivelyFilterExpression(input[key], exp);
                    if (internalResult) {
                        return internalResult;
                    }   
                }
            }
        }

        return null;
     }
  });

** 确保表达式的计算成本不高，在这种情况下，这还不够。