Javascript实现嵌套json数据的深度过滤

Question

我有以下数据结构

tasks = [{
   id: 1,
   name: "task1",
   subtasks: [
      {
         id: 4,
         name: "task2",
         subtasks: [{
            id: 11,
            name: "task to remove",
            completed: false
         }]
      },
      {
         id: 6,
         name: "task to remove",
         subtasks: []
      },
      {
         id: 7,
         name: "parent task to keep",
         subtasks: [{
            id: 11,
            name: "task to keep",
            completed: true
         }]
      }
   ]
},
{
  id: 44,
  name: "task to keep",
  subtasks: [{
    id: 55,
    name: "task to keep",
    completed: true
  },
  {
    id: 66,
    name: "task to delete",
    completed: false
  }
  ]
}
]

由于嵌套级别不受限制，只有叶任务的标志已完成，我只需要过滤掉那些已完成的任务并将其保留在其父任务中。

我查看了lodash，但它似乎没有深层过滤器。我现在正在考虑使用树遍历来过滤任务。

有没有一种简单的方法可以用 lodash 实现这样的事情？

Answer 1

您想要一个 lodash 解决方案。我相信这个递归函数可以解决问题。

function completed (task) {
    // if it is a leaf node, just return true when it is completed
    if (_.has(task,'completed')) {
        return task.completed;
    }

    // if it has subtasks, then use our filter on all the subtasks ...
    if (_.has(task,'subtasks')) {
        task.subtasks = _.filter(task.subtasks, completed);

        // ... and only return true if there are subtasks left after filtering
        return task.subtasks.length;
    }

}

console.log(_.filter(tasks,completed));