javascript - 找到对象数组angularjs的索引

Question

例如我有这个数组:

  $scope.records = [
    {
      "Name" : "Alfreds Futterkiste",
      "Country" : "Germany"
    },
    {
      "Name" : "Berglunds snabbköp",
      "Country" : "Sweden"
    },
    {
      "Name" : "Centro comercial Moctezuma",
      "Country" : "Mexico"
    },
    {
      "Name" : "Ernst Handel",
      "Country" : "Austria"
    }
  ];

如何从对象中获取值索引？以“国家”为例:“奥地利”这个指数是 3

Answer 1

你可以使用 Array.findIndex在最新的浏览器中，但在 Internet Explorer 中不支持此功能，只有 Edge

let $scope = {};

$scope.records = [
    {
      "Name" : "Alfreds Futterkiste",
      "Country" : "Germany"
    },
    {
      "Name" : "Berglunds snabbköp",
      "Country" : "Sweden"
    },
    {
      "Name" : "Centro comercial Moctezuma",
      "Country" : "Mexico"
    },
    {
      "Name" : "Ernst Handel",
      "Country" : "Austria"
    }
];

let index = $scope.records.findIndex( record => record.Country === "Austria" );

console.log(index); // 3

为了支持 IE9 及更高版本，您可以使用 Array.some 代替

var $scope = {};

$scope.records = [{
  "Name": "Alfreds Futterkiste",
  "Country": "Germany"
}, {
  "Name": "Berglunds snabbköp",
  "Country": "Sweden"
}, {
  "Name": "Centro comercial Moctezuma",
  "Country": "Mexico"
}, {
  "Name": "Ernst Handel",
  "Country": "Austria"
}];

var index = -1;

$scope.records.some(function(obj, i) {
  return obj.Country === "Austria" ? index = i : false;
});

console.log(index);