以递归方式从 JavaScript 数组构建 JSON

Question

我想从 http 请求返回的数组中构建一个 JSON 对象，我的实际数组如下所示：

[{

    Description: "Product"

    IsInstanciable: false

    IsMasked: false

    Name: "ProductBase"

    Subclasses: [{

      Description: "Product2"

      IsInstanciable: false

      IsMasked: false

      Name: "ProductBase2",

      Count: 5,

      Subclasses:[]

    },

    {

      Description: "Product3"

      IsInstanciable: false

      IsMasked: false

      Name: "ProductBase3",

      Count: 4,

      Subclasses:[],

    }]

},

{

    Description: "Product4"

    IsInstanciable: false

    IsMasked: false

    Name: "ProductBase4",

    Count: '...',

    Subclasses: [...]

}

我想从上面的数组递归创建一个 JSON 对象。它看起来像这样：

[

  {

    name: 'Product',

    Count: 9,

    children: [

      {name: 'Product2'},

      {name: 'Product3'},

    ]

  }, {

    name: 'Product4',

    children: [

      {

        name: '...',

        Count: 'Sum of Count in all children by level'

        children: [

          {name: '...'},

          {name: '...'},

        ]

      }

    ]

  },

];

这是我在打字稿中的递归函数，但它没有按预期工作。我怎样才能解决这个问题？

recursive(data, stack: TreeNode[]) {

    let elt: TreeNode = {name:'', children: []}

    if(data.Subclasses.length > 0) {

      elt.name = data.Description;

      data.Subclasses.forEach(element => {

        elt.children.push({name: element.Description});

        this.recursive(element, stack);

      });

    }else {

      elt.name = data.Description;

    }

    stack.push(elt);

  }

Answer 1

您可以将 map 函数与递归函数一起使用，如下所示：function MapObject(object) {&nbsp; if(!object || object.length < 0) return [];&nbsp; return object.map(obj => { return {&nbsp; &nbsp; &nbsp; name: obj.Description,&nbsp; &nbsp; &nbsp; children: MapObject(obj.Subclasses)&nbsp; }});}遵循完整的工作示例：var example = [{&nbsp; &nbsp; Description: "Product",&nbsp; &nbsp; IsInstanciable: false,&nbsp; &nbsp; IsMasked: false,&nbsp; &nbsp; Name: "ProductBase",&nbsp; &nbsp; Subclasses: [{&nbsp; &nbsp; &nbsp; Description: "Product2",&nbsp; &nbsp; &nbsp; IsInstanciable: false,&nbsp; &nbsp; &nbsp; IsMasked: false,&nbsp; &nbsp; &nbsp; Name: "ProductBase2",&nbsp; &nbsp; &nbsp; Subclasses:[]&nbsp; &nbsp; },&nbsp; &nbsp; {&nbsp; &nbsp; &nbsp; Description: "Product3",&nbsp; &nbsp; &nbsp; IsInstanciable: false,&nbsp; &nbsp; &nbsp; IsMasked: false,&nbsp; &nbsp; &nbsp; Name: "ProductBase3",&nbsp; &nbsp; &nbsp; Subclasses:[]&nbsp; &nbsp; }]},{&nbsp; &nbsp; Description: "Product4",&nbsp; &nbsp; IsInstanciable: false,&nbsp; &nbsp; IsMasked: false,&nbsp; &nbsp; Name: "ProductBase4"}]function MapObject(object) {&nbsp; if(!object || object.length < 0) return [];&nbsp;&nbsp;&nbsp; return object.map(obj => { return {&nbsp; &nbsp; &nbsp; name: obj.Description,&nbsp; &nbsp; &nbsp; children: MapObject(obj.Subclasses)&nbsp; }});}console.log(MapObject(example));

Answer 2

我会将其分解为几个具有明确职责的独立功能：const sum = (ns) =>&nbsp;&nbsp; ns .reduce ((a, b) => a + Number (b), 0)const getCount = (product) =>&nbsp;&nbsp; (product .Count || 0) + sum ((product .Subclasses || []) .map (getCount))const extract = (product) =>&nbsp;&nbsp; ({&nbsp; &nbsp; name: product .Name,&nbsp; &nbsp; count: getCount (product),&nbsp; &nbsp; children: product .Subclasses .map (extract)&nbsp; })const extractAll = (products) =>&nbsp;&nbsp; products .map (extract)const products = [{"Description": "Product", "IsInstanciable": false, "IsMasked": false, "Name": "ProductBase", "Subclasses": [{"Count": 5, "Description": "Product2", "IsInstanciable": false, "IsMasked": false, "Name": "ProductBase2", "Subclasses": []}, {"Count": 4, "Description": "Product3", "IsInstanciable": false, "IsMasked": false, "Name": "ProductBase3", "Subclasses": []}]}, {"Count": 3, "Description": "Product4", "IsInstanciable": false, "IsMasked": false, "Name": "ProductBase4", "Subclasses": []}]console .log (&nbsp; extractAll (products))（请注意，我更改了 outputcount属性的大小写。它似乎更符合name和children。）我们通过对象递归获取它的Count属性，我们单独递归获取对象的其余部分。虽然可能有一种方法可以将这些结合起来，但我预计代码会更加复杂。请注意，我假设所有Count属性实际上都是数字，尽管上面的示例包含一个字符串。如果您确实有类似 的值"3"，则getCount需要更复杂一些。