Question

我想从数组中的键中获取特定值

   $scope.result = [
{

    "key":"logo_big",
    "value":"/assets/images/aaa.jpg"
    },
    {
    "key":"logo_small",
    "value":"/assets/images/logo94x57Bis.png"
    },
    {
    "key":"project_name",
    "value":"Company"
    },
    {
    "key":"support_email",
    "value":"dev@gmail.com"
    }
    ];

如何获得'logo_big'的值？

$scope.result['logo_big']

返回undefined

Answer 1

您需要遍历数组以查找具有给定键的元素。

或者，如果您的系统支持Array.find（）：

var item = $scope.result.find(function(element) {
    return element.key === 'logo_big';
});
return item && item.value;

不太理想的解决方案是使用过滤器：

var item = $scope.result.filter(function(element) {
    return element.key === 'logo_big';
})[0];
return item && item.value;

Answer 2

const obj = $scope.results.filter(e => e.key == "logo_big")[0];

请参阅MDN Documentation

Answer 3

您首先拥有一个数组，每个数组项都是一个对象，因此如果您想访问，则必须遵循以下内容

for (var i = 0 ; i < $scope.result.length; i++) 
{
  if ($scope.result[i]["key"] == "logo_big") 
  {
   alert("found value");
  } 
}

Answer 4

如果你想以角度方式做，请使用angular.foreach并检查对象的键

angular.forEach($scope.result, function(obj) {
      if (obj.key == "logo_big") {
        $scope.resultObj = obj.value;
        alert($scope.resultObj);
      }

<强>样本

var app = angular.module("app", []);
app.controller("listController", ["$scope", function($scope) {
  $scope.name = 'StackOverflow';
  $scope.result = [{
    "key": "logo_big",
    "value": "/assets/images/aaa.jpg"
  }, {
    "key": "logo_small",
    "value": "/assets/images/logo94x57Bis.png"
  }, {
    "key": "project_name",
    "value": "Company"
  }, {
    "key": "support_email",
    "value": "dev@gmail.com"
  }];

  angular.forEach($scope.result, function(obj) {
    if (obj.key == "logo_big") {
      $scope.resultObj = obj.value;
    }
  });

}]);

<!DOCTYPE html>
<html ng-app="app">

<head>
  <script src="https://code.angularjs.org/1.4.7/angular.js"></script>
  <link rel="stylesheet" href="style.css" />
  <script src="script.js"></script>
</head>

<body ng-controller="listController">
  <h3>Enter an ID</h3>
   <h1> {{resultObj}}</h1>
</body>

</html>

使用Key中的Key获取值 - Angularjs

4 个答案: