计算所选属性为真的数组中的所有嵌套对象

Question

我需要创建一个递归的 function 计数对象，该对象嵌套在selected属性为true的数组中。

 var data = [{"id":1,"code":"1","selected":false,"children":[{"id":4,"code":"1.01","selected":false,"children":[{"id":5,"code":"1.01.001","selected":true,"children":[]},{"id":6,"code":"1.01.002","selected":false,"children":[]},{"id":20,"code":"1.01.003","selected":true,"children":[]}]}]},{"id":2,"code":"2","selected":false,"children":[{"id":7,"code":"2.01","selected":false,"children":[{"id":9,"code":"2.01.001","selected":true,"children":[]},{"id":21,"code":"2.01.002","selected":true,"children":[]},{"id":22,"code":"2.01.003","selected":false,"children":[]}]}]},{"id":3,"code":"3","selected":false,"children":[{"id":8,"code":"3.01","selected":false,"children":[{"id":10,"code":"3.01.01","name":"Sementes","selected":false,"children":[{"id":11,"code":"3.01.01.001","selected":true,"children":[]},{"id":23,"code":"3.01.01.002","selected":false,"children":[]},{"id":24,"code":"3.01.01.003","selected":true,"children":[]}]},{"id":25,"code":"3.01.02","selected":false,"children":[{"id":27,"code":"3.01.02.001","selected":true,"children":[]},{"id":28,"code":"3.01.02.002","selected":false,"children":[]},{"id":29,"code":"3.01.02.003","selected":false,"children":[]}]},{"id":26,"code":"3.01.03","selected":false,"children":[{"id":30,"code":"3.01.03.001","selected":true,"children":[]},{"id":31,"code":"3.01.03.002","selected":true,"children":[]},{"id":32,"code":"3.01.03.003","selected":true,"children":[]},{"id":35,"code":"3.01.03.004","selected":false,"children":[]},{"id":34,"code":"3.01.03.005","selected":false,"children":[]}]}]}]}]; const countSelectedChildren = (arr) => { return arr; } console.log(countSelectedChildren(data))

预期响应：

{
    "id": 3,
    "code": "3",
    "selected": false,
    "selectedChildren": 6,
    "children": [
      {
        "id": 8,
        "code": "3.01",
        "selected": false,
        "selectedChildren": 6,
        "children": [
          {
            "id": 10,
            "code": "3.01.01",
            "name": "Sementes",
            "selected": false,
            "selectedChildren": 2,
            "children": [
              {
                "id": 11,
                "code": "3.01.01.001",
                "selected": true,
                "children": []
              },
              {
                "id": 23,
                "code": "3.01.01.002",
                "selected": false,
                "children": []
              },
              {
                "id": 24,
                "code": "3.01.01.003",
                "selected": true,
                "children": []
              }
            ]
          },
          {
            "id": 25,
            "code": "3.01.02",
            "selected": false,
            "selectedChildren": 1,
            "children": [
              {
                "id": 27,
                "code": "3.01.02.001",
                "selected": true,
                "children": []
              },
              {
                "id": 28,
                "code": "3.01.02.002",
                "selected": false,
                "children": []
              },
              {
                "id": 29,
                "code": "3.01.02.003",
                "selected": false,
                "children": []
              }
            ]
          },
          {
            "id": 26,
            "code": "3.01.03",
            "selected": false,
            "selectedChildren": 3,
            "children": [
              {
                "id": 30,
                "code": "3.01.03.001",
                "selected": true,
                "children": []
              },
              {
                "id": 31,
                "code": "3.01.03.002",
                "selected": true,
                "children": []
              },
              {
                "id": 32,
                "code": "3.01.03.003",
                "selected": true,
                "children": []
              },
              {
                "id": 35,
                "code": "3.01.03.004",
                "selected": false,
                "children": []
              },
              {
                "id": 34,
                "code": "3.01.03.005",
                "selected": false,
                "children": []
              }
            ]
          }
        ]
      }
    ]
  }

你能帮我创建这个递归 function 吗？

const countSelectedChildren = (arr) => {

return arr;
}

感谢您的帮助！

Answer 1

 const countSelectedChildren = (data) => { let length = 0; for (item of data) { item.selected && (length++) let child_length = countSelectedChildren(item.children || [])[1]; length += child_length; item.selectedChildren = child_length; } return [data, length]; }

Answer 2

您可以对数组采用递归 function 并返回具有计数属性和子数组的 object。

 const addSelected = array => { let selectedChildren = 0; const children = array.map(({ children, ...o }) => { if (o.selected) selectedChildren++; const temp = addSelected(children); selectedChildren += temp.selectedChildren || 0; return {...o, ...temp }; }); return children.length? { selectedChildren, children }: { children }; }, data = [{ id: 1, code: "1", selected: false, children: [{ id: 4, code: "1.01", selected: false, children: [{ id: 5, code: "1.01.001", selected: true, children: [] }, { id: 6, code: "1.01.002", selected: false, children: [] }, { id: 20, code: "1.01.003", selected: true, children: [] }] }] }, { id: 2, code: "2", selected: false, children: [{ id: 7, code: "2.01", selected: false, children: [{ id: 9, code: "2.01.001", selected: true, children: [] }, { id: 21, code: "2.01.002", selected: true, children: [] }, { id: 22, code: "2.01.003", selected: false, children: [] }] }] }, { id: 3, code: "3", selected: false, children: [{ id: 8, code: "3.01", selected: false, children: [{ id: 10, code: "3.01.01", name: "Sementes", selected: false, children: [{ id: 11, code: "3.01.01.001", selected: true, children: [] }, { id: 23, code: "3.01.01.002", selected: false, children: [] }, { id: 24, code: "3.01.01.003", selected: true, children: [] }] }, { id: 25, code: "3.01.02", selected: false, children: [{ id: 27, code: "3.01.02.001", selected: true, children: [] }, { id: 28, code: "3.01.02.002", selected: false, children: [] }, { id: 29, code: "3.01.02.003", selected: false, children: [] }] }, { id: 26, code: "3.01.03", selected: false, children: [{ id: 30, code: "3.01.03.001", selected: true, children: [] }, { id: 31, code: "3.01.03.002", selected: true, children: [] }, { id: 32, code: "3.01.03.003", selected: true, children: [] }, { id: 35, code: "3.01.03.004", selected: false, children: [] }, { id: 34, code: "3.01.03.005", selected: false, children: [] }] }] }] }], result = addSelected(data).children; console.log(result);

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Answer 3

这是一个相当简单的递归来做到这一点：

 const sum = (ns) => ns.reduce ((a, b) => a + b, 0) const countSelectedChildren = (xs) => xs.map (({children = [], ...rest}, _, __, kids = countSelectedChildren (children)) => ({...rest, ...(children.length? {selectedChildren: sum (kids.map (x => (x.selected? 1: 0) + (x.selectedChildren || 0)))}: {} ), children: kids, })) const data = [{"id":1,"code":"1","selected":false,"children":[{"id":4,"code":"1.01","selected":false,"children":[{"id":5,"code":"1.01.001","selected":true,"children":[]},{"id":6,"code":"1.01.002","selected":false,"children":[]},{"id":20,"code":"1.01.003","selected":true,"children":[]}]}]},{"id":2,"code":"2","selected":false,"children":[{"id":7,"code":"2.01","selected":false,"children":[{"id":9,"code":"2.01.001","selected":true,"children":[]},{"id":21,"code":"2.01.002","selected":true,"children":[]},{"id":22,"code":"2.01.003","selected":false,"children":[]}]}]},{"id":3,"code":"3","selected":false,"children":[{"id":8,"code":"3.01","selected":false,"children":[{"id":10,"code":"3.01.01","name":"Sementes","selected":false,"children":[{"id":11,"code":"3.01.01.001","selected":true,"children":[]},{"id":23,"code":"3.01.01.002","selected":false,"children":[]},{"id":24,"code":"3.01.01.003","selected":true,"children":[]}]},{"id":25,"code":"3.01.02","selected":false,"children":[{"id":27,"code":"3.01.02.001","selected":true,"children":[]},{"id":28,"code":"3.01.02.002","selected":false,"children":[]},{"id":29,"code":"3.01.02.003","selected":false,"children":[]}]},{"id":26,"code":"3.01.03","selected":false,"children":[{"id":30,"code":"3.01.03.001","selected":true,"children":[]},{"id":31,"code":"3.01.03.002","selected":true,"children":[]},{"id":32,"code":"3.01.03.003","selected":true,"children":[]},{"id":35,"code":"3.01.03.004","selected":false,"children":[]},{"id":34,"code":"3.01.03.005","selected":false,"children":[]}]}]}]}]; console.log (countSelectedChildren (data))

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对于输入数组中的每个元素，首先在任何子节点上重复出现，然后计算我们当前节点的selectedChildren ，我们将每个子节点的结果相加，如果它被选中，则为每个节点加一个。 然后我们简单地将一个新的 object 和selectedChildren组合在一起，如果我们有实际的孩子， children是我们递归的结果，以及我们元素的属性的 rest。

虽然我们可以内联对sum助手 function 的一次调用，但这是我们可能经常需要的东西，因此将它分开会更简洁。

Answer 4

我会这样处理

    const countSelectedChildren = (inArr) => {
        
        const outArr = [];
        
        inArr.forEach(row => {
        
          //  simply count all chilren with selected=true
          row.SelectedChildren = row.children.filter(row => row.selected).length;
        
          //  if there are children, call this function on them
          if (row.children.length) {
             row.children = countSelectedChildren(row.children);
          }
          
          outArr.push(row);
        });
        
        return outArr;
        
    }

 const data = [ { "id": 1, "code": "1", "selected": false, "children": [ { "id": 4, "code": "1.01", "selected": false, "children": [ { "id": 5, "code": "1.01.001", "selected": true, "children": [] }, { "id": 6, "code": "1.01.002", "selected": false, "children": [] }, { "id": 20, "code": "1.01.003", "selected": true, "children": [] } ] } ] }, { "id": 2, "code": "2", "selected": false, "children": [ { "id": 7, "code": "2.01", "selected": false, "children": [ { "id": 9, "code": "2.01.001", "selected": true, "children": [] }, { "id": 21, "code": "2.01.002", "selected": true, "children": [] }, { "id": 22, "code": "2.01.003", "selected": false, "children": [] } ] } ] }, { "id": 3, "code": "3", "selected": false, "children": [ { "id": 8, "code": "3.01", "selected": false, "children": [ { "id": 10, "code": "3.01.01", "name": "Sementes", "selected": false, "children": [ { "id": 11, "code": "3.01.01.001", "selected": true, "children": [] }, { "id": 23, "code": "3.01.01.002", "selected": false, "children": [] }, { "id": 24, "code": "3.01.01.003", "selected": true, "children": [] } ] }, { "id": 25, "code": "3.01.02", "selected": false, "children": [ { "id": 27, "code": "3.01.02.001", "selected": true, "children": [] }, { "id": 28, "code": "3.01.02.002", "selected": false, "children": [] }, { "id": 29, "code": "3.01.02.003", "selected": false, "children": [] } ] }, { "id": 26, "code": "3.01.03", "selected": false, "children": [ { "id": 30, "code": "3.01.03.001", "selected": true, "children": [] }, { "id": 31, "code": "3.01.03.002", "selected": true, "children": [] }, { "id": 32, "code": "3.01.03.003", "selected": true, "children": [] }, { "id": 35, "code": "3.01.03.004", "selected": false, "children": [] }, { "id": 34, "code": "3.01.03.005", "selected": false, "children": [] } ] } ] } ] } ]; const countSelectedChildren = (inArr) => { const outArr = []; inArr.forEach(row => { // simply count all chilren with selected=true row.SelectedChildren = row.children.filter(row => row.selected).length; // if there are children, call this function on them if (row.children.length) { row.children = countSelectedChildren(row.children); } outArr.push(row); }); return outArr; } console.log(countSelectedChildren(data))