How to use all records JS parent node traversal to find the breadth

We often encountered in actual business scenarios work in such a scene, obtaining data tree node in a node, and the father of all father nodes, such a scenario is not recommended depth traversal, using breadth traversal can be found more quickly.

1, Case Commentary

For example, the tree looks like this:

Data Tree is this:

Is our common data and appearance of the tree.

2, business requirements

[5] In the extraction test behind a new node requires
1) the incoming interface requires the parent of the current node;
2) after the new reacquisition tree data, expanded by default all of the parent

3, and description code implementation

Ideas:
1) setting a line array parentIdsQueuewill start queuing tree data;
2) if the current node has children, the child nodes descending added to the queue, because the time is traversed from the start of the first data;
3) if the current data have children nodes before children queued data into the parent node parentArr; and
4) If a node is found, if the node is the first layer, can be directly obtained; if included parentArr, is parentArrin all its parent level node

More than just words to the implementation code

// id 指的是当前点击的节点id;
findParentNode (id) {
      // 初始化所需数据
      this.firstParentObj = {}; // 记录直系父级的名称和id即接口要传的数据
      this.parentIds = []; // 记录所有的父级ids
      this.parentIdsQueue = []; // 记录排队的
       
      // 将树放到排队系列
      this.parentIdsQueue = this.treeData;

      // 开始遍历排队的树
      while (this.parentIdsQueue.length) {
        //抽取第一个排队的数据 
        let item = this.parentIdsQueue.shift();

        let { children } = item;
        if (item.id === id) {
          // 第一层就找到了
          if (!item.parentArr) {
            this.firstParentObj = {
              id: item.id,
              name: item.title
            };
            this.parentIds = [item.id];
          } else {
            // 获取当前节点的parentArr
            let len = item.parentArr.length;
            this.firstParentObj = item.parentArr[len - 1];
            item.parentArr.forEach(a => {
              this.parentIds.push(a.id);
            });

            this.parentIds.push(item.id);
          }

          // 结束遍历
          this.parentIdsQueue = [];
          break;
        } else if (children && children.length) {
          let len = children.length;
          for (let i = len - 1; i >= 0; i--) {
            // 新建一个数组用于记录它的父亲节点
            children[i].parentArr = [];

            // 把它的历史父亲节点们先放入
            if (item.parentArr) {
              children[i].parentArr = children[i].parentArr.concat(
                item.parentArr
              );
            }
            
            // 再放入当前的父亲节点
            children[i].parentArr.push({
              id: item.id,
              name: item.title
            });

            // 加入到排队序列中
            this.parentIdsQueue.unshift(children[i]);
          }
        }
      }
    }

5 results presentation

We add nodes in the example cited in the text before, are now required to print out the data

     console.log("测试抽取5的所有父亲",item.parentArr);
     console.log("接口所需的父亲节点数据",this.firstParentObj);
     console.log("设置树展开所需的所有父亲节点数据节点id", this.parentIds);

As shown, we have achieved related functions. As to expand the tree, all the parent node acquired id traverse the tree in parentIdssettings that expandis true can be.