JavaScript如何通过子节点id查询树形结构的完整父节点路径

你原有代码的问题主要出在这几点：

• 全局声明的parent数组没有回溯逻辑，遍历到错误分支时推入的节点id不会被移除，会导致路径冗余
• 找到目标节点时，没有把当前节点自身的id加入路径
• 递归调用后没有对返回值做判断，即使子层找到目标也不会向上返回结果，导致最终拿到undefined
• 没有处理遍历完所有子节点都没找到的情况，路径不会回滚

const findNodePath = (tree, targetId) => {
  // 递归遍历函数，path用来记录当前遍历路径
  const dfs = (nodes, path) => {
    for (const node of nodes) {
      // 先把当前节点id加入路径
      path.push(node.attr.id)
      // 命中目标直接返回路径副本
      if (node.attr.id === targetId) {
        return [...path]
      }
      // 有子节点就递归查找子层
      if (node.children?.length) {
        const childRes = dfs(node.children, path)
        // 子层找到结果就向上返回
        if (childRes) return childRes
      }
      // 当前分支没找到，回溯：弹出当前节点id
      path.pop()
    }
    // 当前分支所有节点都没找到，返回null
    return null
  }
  const pathArr = dfs(tree, [])
  // 找到路径就按要求拼接成字符串，没找到返回空字符串
  return pathArr ? pathArr.join(' -> ') : ''
}

// 测试用例
let arr = [{"attr": {"id": "nf-bsf","name": "BSF","sequence": 1},"children": [{"attr": {"id": "bsfGeneralConfig","name": "General Configurations","sequence": 10},"children": [{"attr": {"id": "services/bsf/bsfGlobalCfg","name": "General Settings","topic": "bsf.global.cfg","sequence": 10}}, {"attr": {"id": "configurations/bsf/sbiErrorCodes","name": "SBI Error Codes","topic": "bsf.sbi.errorcodes","sequence": 20}}]}, {"attr": {"id": "services/bsf/conLoggingLevel","name": "Logging Level","topic": "consistent.logging.cfg.topics","sequence": 20}}, {"attr": {"id": "bsfServices","name": "Service Configurations","sequence": 30},"children": [{"attr": {"id": "services/bsf/managementService","name": "Management Service","topic": "bsf.managementservice","sequence": 10}}]}, {"attr": {"id": "bsfConfig","name": "Diameter Configurations","sequence": 40},"children": [{"attr": {"id": "services/bsf/diamSetting","name": "Settings","topic": "common.diamsetting","sequence": 10}}, {"attr": {"id": "configurations/bsf/diamPeerNode","name": "Peer Nodes","topic": "common.public.diampeernode","sequence": 20}}, {"attr": {"id": "services/bsf/diamRoutingTable","name": "Routing Table","topic": "common.public.diamroutingtable","sequence": 30}}, {"attr": {"id": "configurations/bsf/diamLoadShedding","name": "Load Shedding Profiles","topic": "common.public.diamloadshedding","sequence": 40}}, {"attr": {"id": "configurations/bsf/diamMessagePriority","name": "Message Priority Profiles","topic": "common.public.diammessagepriority","sequence": 50}}]}, {"attr": {"id": "bsf-sessionViewer","name": "Session Viewer","sequence": 50}}, {"attr": {"id": "administration","name": "Administration","sequence": 60},"children": [{"attr": {"id": "bsfBulkExportImport","name": "Export & Import","sequence": 10}}]}]}];

console.log(findNodePath(arr, "services/bsf/diamSetting")) 
// 输出结果：nf-bsf -> bsfConfig -> services/bsf/diamSetting

• 采用带回溯的深度优先遍历，每进入一个节点就把id加入当前路径，遍历完当前节点的所有子分支都没找到目标，就把当前节点id从路径中移除，避免干扰其他分支的遍历
• 命中目标时直接返回路径的副本，避免后续回溯操作修改最终结果
• 递归层只要拿到子层返回的有效路径就直接向上传递，终止其他不必要的遍历

内容的提问来源于stack exchange，提问作者misbha afreen