从平面数组javascript生成树 [英] Generate Tree from flat Array javascript

问题描述

我有一个数组如下

arr = [
    {
        id: 1,
        name: 'Node1',
        level: 1
    },
    {
        id: 2,
        name: 'Node2',
        level: 2
    },
    {
        id: 3,
        name: 'Node3',
        level: 3
    },
    {
        id: 4,
        name: 'Node4',
        level: 4
    },
    {
        id: 5,
        name: 'Node5',
        level: 5
    },
];

我想基于级别生成树.输出应为

I want to generate tree on basis of level. Output should be

tree = 
{
    id: 1,
    name: 'Node1',
    level: 1,
    nodes: {
        id: 2,
        name: 'Node2',
        level: 2,
        nodes : {
            id: 3,
            name: 'Node3',
            level: 3,
            nodes: {
                id: 4,
                name: 'Node4',
                level: 4,
                nodes : {
                    id: 5,
                    name: 'Node5',
                    level: 5,
                    nodes: []
                }
            }
        }
    }
}

每当节点= []时，表示它是最后一个节点.数组的顺序可以是任何东西，但树应该基于级别构建.

whenever nodes = [], that means it's the last nodes. the order of array can be anything but tree should be built on basis of level.

推荐答案

您可以使用level属性指示辅助数组中的嵌套位置.然后迭代数据并在必要时构建子节点.

You could use the level property for indicating the nested position in a helper array. Then iterate the data and build children nodes if necessary.

function getTree(array) {
    var levels = [{}];
    array.forEach(function (a) {
        levels.length = a.level;
        levels[a.level - 1].nodes = levels[a.level - 1].nodes || [];
        levels[a.level - 1].nodes.push(a);
        levels[a.level] = a;
    });
    return levels[0].nodes;
}

console.log(getTree([{ id: 1, name: 'Node1', level: 1 }, { id: 2, name: 'Node2', level: 2 }, { id: 3, name: 'Node3', level: 3 }, { id: 4, name: 'Node4', level: 4 }, { id: 5, name: 'Node5', level: 5 }]));
console.log(getTree([{ id: 1, name: 'Node 1', level: 1 }, { id: 2, name: 'Node 1.1', level: 2 }, { id: 3, name: 'Node 1.1.1', level: 3 }, { id: 4, name: 'Node 1.1.1.1', level: 4 }, { id: 5, name: 'Node 1.2', level: 2 }, { id: 6, name: 'Node 1.2.1', level: 3 }, ]));

.as-console-wrapper { max-height: 100% !important; top: 0; }

这篇关于从平面数组javascript生成树的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！