javascript - 在构造函数中遍历对象内部的对象？

Question

在构造函数中，我试图创建一个对象。

在该对象中，我已经为某些数组使用了 map 函数。

当我尝试遍历一个对象时出现了挑战，因为我不能在对象上使用 map 函数。我也试过在这个对象中使用 for in 函数，但看起来，在对象创建中使用 for in 是无效的 JS。

我的目标是遍历 individualData 对象(就像数组的普通映射函数一样)。

我尝试将 data: data.individualData 移动到 map 函数中。这对我的预期结果不起作用。

这是我的代码:

labelsArray = ['Breakfast', 'Lunch', 'Dinner'];

data = {
  miniLabelsArray: ['Egg', 'Soup', 'Steak'],
  type: ['Vegetarian', 'Vegan', 'Normal'],
  individualData: [{
    John: ['1', '2', '3'],
    Paul: ['10', '20', '30'],
    Kate: ['100', '200', '300']
  }]
};

function CreateData(data, someNewObj) {
  
  this.someNewObj = {
    labels: labelsArray,
    datasets: 
      data.miniLabelsArray.map((miniLabelsArray, i) => ({
        miniLabel: data.miniLabelsArray[i],
        type: data.type[i],
        })),
        data: data.individualData
    };
  };

var testing = new CreateData(data);

console.log('testing', testing.someNewObj);

https://codepen.io/anon/pen/qoMdoe?editors=1111

预期结果:

 ...
  "datasets": [
    {
      "miniLabel": "Egg",
      "type": "Vegetarian",
      "data": ["1", "2", "3"]       // DIFFERENCE HERE
    },
    {
      "miniLabel": "Soup",
      "type": "Vegan",
      "data": ["10", "20", "30"]       // DIFFERENCE HERE
    },
    {
      "miniLabel": "Steak",
      "type": "Normal",
      "data" :["100", "200", "300"]       // DIFFERENCE HERE
    }
  ...

谢谢

Answer 1

我将您的方法更新为 This。

datasets: data.miniLabelsArray.map((value, index)=>({
  miniLabel: value,
  type: data.type[index],
  data: data.individualData[0][keys[index]]
}))

这里重要的是 var keys = Object.keys(data.individualData[0])

和数据:data.individualData[0][keys[index]]

labelsArray = ['Breakfast', 'Lunch', 'Dinner'];

data = {
  miniLabelsArray: ['Egg', 'Soup', 'Steak'],
  type: ['Vegetarian', 'Vegan', 'Normal'],
  individualData: [{
    John: ['1', '2', '3'],
    Paul: ['10', '20', '30'],
    Kate: ['100', '200', '300']
  }]
};

function CreateData(data, someNewObj) {
  //get keys from [individualData] property
  var keys = Object.keys(data.individualData[0])
  this.someNewObj = {
    labels: labelsArray,
    // here we map every [miniLabelsArray] value and get the [type] and [individualData] depending on the index that we are.
    datasets: data.miniLabelsArray.map((value, index)=>({
      miniLabel: value,
      type: data.type[index],
      // here we get the real key of [data.individualData] using the key we took at the beginning like this : keys[index], and with that key we get the value in [data.individualData[0]]
      data: data.individualData[0][keys[index]]
    }))
      
    };
  };

var testing = new CreateData(data);

console.log('testing', testing.someNewObj);