我有一个复杂的json文件,我必须处理javascript使其分层,以便稍后构建树。 json的每个条目都有: Id:唯一的Id, parentId:父节点的id(如果节点是树的根,则为0) Level:树的深度级别

json数据已经“有序”。我的意思是,一个条目在它上面有一个父节点或兄弟节点,在它下面有一个子节点或兄弟节点。

输入:

{
    "People": [
        {
            "id": "12",
            "parentId": "0",
            "text": "Man",
            "level": "1",
            "children": null
        },
        {
            "id": "6",
            "parentId": "12",
            "text": "Boy",
            "level": "2",
            "children": null
        },
                {
            "id": "7",
            "parentId": "12",
            "text": "Other",
            "level": "2",
            "children": null
        },
        {
            "id": "9",
            "parentId": "0",
            "text": "Woman",
            "level": "1",
            "children": null
        },
        {
            "id": "11",
            "parentId": "9",
            "text": "Girl",
            "level": "2",
            "children": null
        }
    ],
    "Animals": [
        {
            "id": "5",
            "parentId": "0",
            "text": "Dog",
            "level": "1",
            "children": null
        },
        {
            "id": "8",
            "parentId": "5",
            "text": "Puppy",
            "level": "2",
            "children": null
        },
        {
            "id": "10",
            "parentId": "13",
            "text": "Cat",
            "level": "1",
            "children": null
        },
        {
            "id": "14",
            "parentId": "13",
            "text": "Kitten",
            "level": "2",
            "children": null
        },
    ]
}

预期产量:

{
    "People": [
        {
            "id": "12",
            "parentId": "0",
            "text": "Man",
            "level": "1",
            "children": [
                {
                    "id": "6",
                    "parentId": "12",
                    "text": "Boy",
                    "level": "2",
                    "children": null
                },
                {
                    "id": "7",
                    "parentId": "12",
                    "text": "Other",
                    "level": "2",
                    "children": null
                }   
            ]
        },
        {
            "id": "9",
            "parentId": "0",
            "text": "Woman",
            "level": "1",
            "children":
            {

                "id": "11",
                "parentId": "9",
                "text": "Girl",
                "level": "2",
                "children": null
            }
        }

    ],    

    "Animals": [
        {
            "id": "5",
            "parentId": "0",
            "text": "Dog",
            "level": "1",
            "children": 
                {
                    "id": "8",
                    "parentId": "5",
                    "text": "Puppy",
                    "level": "2",
                    "children": null
                }
        },
        {
            "id": "10",
            "parentId": "13",
            "text": "Cat",
            "level": "1",
            "children": 
            {
                "id": "14",
                "parentId": "13",
                "text": "Kitten",
                "level": "2",
                "children": null
            }
        }

    ]
}

当前回答

它可能是有用的包列表到树 安装:

bower install list-to-tree --save

or

npm install list-to-tree --save

例如,有列表:

var list = [
  {
    id: 1,
    parent: 0
  }, {
    id: 2,
    parent: 1
  }, {
    id: 3,
    parent: 1
  }, {
    id: 4,
    parent: 2
  }, {
    id: 5,
    parent: 2
  }, {
    id: 6,
    parent: 0
  }, {
    id: 7,
    parent: 0
  }, {
    id: 8,
    parent: 7
  }, {
    id: 9,
    parent: 8
  }, {
    id: 10,
    parent: 0
  }
];

使用包列表到树:

var ltt = new LTT(list, {
  key_id: 'id',
  key_parent: 'parent'
});
var tree = ltt.GetTree();

结果:

[{
  "id": 1,
  "parent": 0,
  "child": [
    {
      "id": 2,
      "parent": 1,
      "child": [
        {
          "id": 4,
          "parent": 2
        }, {
          "id": 5, "parent": 2
        }
      ]
    },
    {
      "id": 3,
      "parent": 1
    }
  ]
}, {
  "id": 6,
  "parent": 0
}, {
  "id": 7,
  "parent": 0,
  "child": [
    {
      "id": 8,
      "parent": 7,
      "child": [
        {
          "id": 9,
          "parent": 8
        }
      ]
    }
  ]
}, {
  "id": 10,
  "parent": 0
}];

其他回答

也可以使用lodashjs(v4.x)

function buildTree(arr){
  var a=_.keyBy(arr, 'id')
  return _
   .chain(arr)
   .groupBy('parentId')
   .forEach(function(v,k){ 
     k!='0' && (a[k].children=(a[k].children||[]).concat(v));
   })
   .result('0')
   .value();
}

将节点数组转换为树

ES6函数转换数组节点(由父ID相关)到树结构:

/**
 * Convert nodes list related by parent ID - to tree.
 * @syntax getTree(nodesArray [, rootID [, propertyName]])
 *
 * @param {Array} arr   Array of nodes
 * @param {integer} id  Defaults to 0
 * @param {string} p    Property name. Defaults to "parent_id"
 * @returns {Object}    Nodes tree
 */

const getTree = (arr, p = "parent_id") => arr.reduce((o, n) => {

  if (!o[n.id]) o[n.id] = {};
  if (!o[n[p]]) o[n[p]] = {};
  if (!o[n[p]].nodes) o[n[p]].nodes= [];
  if (o[n.id].nodes) n.nodes= o[n.id].nodes;

  o[n[p]].nodes.push(n);
  o[n.id] = n;

  return o;
}, {});

从节点树生成HTML列表

有了我们的树,这里有一个递归函数来构建UL > LI元素:

/**
 * Convert Tree structure to UL>LI and append to Element
 * @syntax getTree(treeArray [, TargetElement [, onLICreatedCallback ]])
 *
 * @param {Array} tree Tree array of nodes
 * @param {Element} el HTMLElement to insert into
 * @param {function} cb Callback function called on every LI creation
 */

const treeToHTML = (tree, el, cb) => el.append(tree.reduce((ul, n) => {
  const li = document.createElement('li');

  if (cb) cb.call(li, n);
  if (n.nodes?.length) treeToHTML(n.nodes, li, cb);

  ul.append(li);
  return ul;
}, document.createElement('ul')));

演示时间

下面是一个使用上述两个函数的线性节点数组的例子:

const getTree = (arr, p = "parent_id") => arr.reduce((o, n) => { if (!o[n.id]) o[n.id] = {}; if (!o[n[p]]) o[n[p]] = {}; if (!o[n[p]].nodes) o[n[p]].nodes = []; if (o[n.id].nodes) n.nodes = o[n.id].nodes; o[n[p]].nodes.push(n); o[n.id] = n; return o; }, {}); const treeToHTML = (tree, el, cb) => el.append(tree.reduce((ul, n) => { const li = document.createElement('li'); if (cb) cb.call(li, n); if (n.nodes?.length) treeToHTML(n.nodes, li, cb); ul.append(li); return ul; }, document.createElement('ul'))); // DEMO TIME: const nodesList = [ {id: 10, parent_id: 4, text: "Item 10"}, // PS: Order does not matters {id: 1, parent_id: 0, text: "Item 1"}, {id: 4, parent_id: 0, text: "Item 4"}, {id: 3, parent_id: 5, text: "Item 3"}, {id: 5, parent_id: 4, text: "Item 5"}, {id: 2, parent_id: 1, text: "Item 2"}, ]; const myTree = getTree(nodesList)[0].nodes; // Get nodes of Root (0) treeToHTML(myTree, document.querySelector("#tree"), function(node) { this.textContent = `(${node.parent_id} ${node.id}) ${node.text}`; this._node = node; this.addEventListener('click', clickHandler); }); function clickHandler(ev) { if (ev.target !== this) return; console.clear(); console.log(this._node.id); }; <div id="tree"></div>

正如@Sander提到的,@Halcyon的答案假设一个预先排序的数组,下面的不是。(然而,它假设你已经加载了underscore.js -尽管它可以用香草javascript编写):

Code

// Example usage var arr = [ {'id':1 ,'parentid' : 0}, {'id':2 ,'parentid' : 1}, {'id':3 ,'parentid' : 1}, {'id':4 ,'parentid' : 2}, {'id':5 ,'parentid' : 0}, {'id':6 ,'parentid' : 0}, {'id':7 ,'parentid' : 4} ]; unflatten = function( array, parent, tree ){ tree = typeof tree !== 'undefined' ? tree : []; parent = typeof parent !== 'undefined' ? parent : { id: 0 }; var children = _.filter( array, function(child){ return child.parentid == parent.id; }); if( !_.isEmpty( children ) ){ if( parent.id == 0 ){ tree = children; }else{ parent['children'] = children } _.each( children, function( child ){ unflatten( array, child ) } ); } return tree; } tree = unflatten( arr ); document.body.innerHTML = "<pre>" + (JSON.stringify(tree, null, " ")) <script src="https://cdnjs.cloudflare.com/ajax/libs/underscore.js/1.9.1/underscore-min.js"></script>

需求

它假设属性'id'和'parentid'分别表示id和父id。必须有父ID为0的元素,否则将返回一个空数组。孤儿元素及其后代“丢失”

http://jsfiddle.net/LkkwH/1/

有同样的问题,但我不能确定数据是否已排序。我不能使用第三方库,所以这只是香草Js;输入数据可以从@Stephen的例子中获取;

var arr = [ {'id':1 ,'parentid' : 0}, {'id':4 ,'parentid' : 2}, {'id':3 ,'parentid' : 1}, {'id':5 ,'parentid' : 0}, {'id':6 ,'parentid' : 0}, {'id':2 ,'parentid' : 1}, {'id':7 ,'parentid' : 4}, {'id':8 ,'parentid' : 1} ]; function unflatten(arr) { var tree = [], mappedArr = {}, arrElem, mappedElem; // First map the nodes of the array to an object -> create a hash table. for(var i = 0, len = arr.length; i < len; i++) { arrElem = arr[i]; mappedArr[arrElem.id] = arrElem; mappedArr[arrElem.id]['children'] = []; } for (var id in mappedArr) { if (mappedArr.hasOwnProperty(id)) { mappedElem = mappedArr[id]; // If the element is not at the root level, add it to its parent array of children. if (mappedElem.parentid) { mappedArr[mappedElem['parentid']]['children'].push(mappedElem); } // If the element is at the root level, add it to first level elements array. else { tree.push(mappedElem); } } } return tree; } var tree = unflatten(arr); document.body.innerHTML = "<pre>" + (JSON.stringify(tree, null, " "))

JS小提琴

平面阵列到树

它可能是有用的包列表到树 安装:

bower install list-to-tree --save

or

npm install list-to-tree --save

例如,有列表:

var list = [
  {
    id: 1,
    parent: 0
  }, {
    id: 2,
    parent: 1
  }, {
    id: 3,
    parent: 1
  }, {
    id: 4,
    parent: 2
  }, {
    id: 5,
    parent: 2
  }, {
    id: 6,
    parent: 0
  }, {
    id: 7,
    parent: 0
  }, {
    id: 8,
    parent: 7
  }, {
    id: 9,
    parent: 8
  }, {
    id: 10,
    parent: 0
  }
];

使用包列表到树:

var ltt = new LTT(list, {
  key_id: 'id',
  key_parent: 'parent'
});
var tree = ltt.GetTree();

结果:

[{
  "id": 1,
  "parent": 0,
  "child": [
    {
      "id": 2,
      "parent": 1,
      "child": [
        {
          "id": 4,
          "parent": 2
        }, {
          "id": 5, "parent": 2
        }
      ]
    },
    {
      "id": 3,
      "parent": 1
    }
  ]
}, {
  "id": 6,
  "parent": 0
}, {
  "id": 7,
  "parent": 0,
  "child": [
    {
      "id": 8,
      "parent": 7,
      "child": [
        {
          "id": 9,
          "parent": 8
        }
      ]
    }
  ]
}, {
  "id": 10,
  "parent": 0
}];