对象中的多维数组

Question

请仔细阅读这个javascript对象:

var obj = [{
  id: "A",
  children: [{
    id: "B",
    children: [{
      id: "C",
      children: [{
        id: "D",
        children: [{
          id: "E",
          children: [{
            id: "F"
          }]
        }]
      }, {
        id: "G",
        children: {
          id: "H"
        }
      }]
    }, {
      id: "I"
    }]
  }, {
    id: "J",
    children: [{
      id: "K"
    }]
  }]
}, {
  id: "L"
}, {
  id: "M",
  children: {
    id: "N",
    children: [{
      id: "O"
    }]
  }
}, {
  id: "P"
}];

如何编写JavaScript代码以递归方式解析它并在控制台中打印所有ID,以便输出如下所示:

A
B
C
D
E
F
G
H
I
J
K
L
M
N
O
P

这是我能达到的目标.之后我想不出任何逻辑.

for ( i=0 ; i < obj.length ; i++ ){
         var objId = obj[i];
         for( j=i; j<1 ; j++){
             console.log(obj[j].id);
             console.log(obj[j].children[j].id);
         }
     }

我不明白应该在这里应用什么逻辑.帮忙.

Answer 1

您可以使用深度优先搜索算法的迭代和递归方法.

编辑:为子对象扩展.

var data = [{ id: "A", children: [{ id: "B", children: [{ id: "C", children: [{ id: "D", children: [{ id: "E", children: [{ id: "F" }] }] }, { id: "G", children: { id: "H" } }] }, { id: "I" }] }, { id: "J", children: [{ id: "K" }] }] }, { id: "L" }, { id: "M", children: { id: "N", children: [{ id: "O" }] } }, { id: "P" }];

data.forEach(function iter(a) {
    console.log(a.id);
    if (Array.isArray(a.children)) {
        a.children.forEach(iter);
        return;
    }
    if (a.children && typeof a.children === 'object') { // omit this part
        iter(a.children);                               // if children is
    }                                                   // always an array
});

此版本收集所有必需的数据并将其返回到数组中.

var data = [{ id: "A", children: [{ id: "B", children: [{ id: "C", children: [{ id: "D", children: [{ id: "E", children: [{ id: "F" }] }] }, { id: "G", children: { id: "H" } }] }, { id: "I" }] }, { id: "J", children: [{ id: "K" }] }] }, { id: "L" }, { id: "M", children: { id: "N", children: [{ id: "O" }] } }, { id: "P" }],
    result = data.reduce(function iter(r, o) {
        r.push(o.id);
        if (Array.isArray(o.children)) {
            return o.children.reduce(iter, r);
        }
        if (o.children && typeof o.children === 'object') { // omit this part
            return iter(r, o.children);                     // if children is
        }                                                   // always an array
        return r;
    }, []);

console.log(result);

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