javascript - 如果 JavaScript ES6 中为空，则从对象中删除子数组

Question

我有一个看起来像这样的对象:

const inputObject = {
    "startDate": {
        "$gte": "2017-03-29T00:00:00.000Z",
        "$lte": "2017-08-20T00:00:00.000Z"
    },
    "$and": [
        { "$or": [
                {"details.thing": { "$in": [ "01" ] } },
                {"details.thing": { "$in": [ "01" ] } },
                {"details.thing": { "$in" : [ "01" ] } },
                {"details.thing": { "$in" : [ "01" ] } }
            ]
        },
        {
            "$or": []
        },
        {
            "$or": []
        }
    ]
}

我需要开发一个函数来删除任何存在的空 { "$or": [] }, 子数组。我的预期输出是:

const outputObject = {
    "startDate": {
        "$gte": "2017-03-29T00:00:00.000Z",
        "$lte": "2017-08-20T00:00:00.000Z"
    },
    "$and": [
        { "$or": [
                {"details.thing": { "$in": [ "01" ] } },
                {"details.thing": { "$in": [ "01" ] } },
                {"details.thing": { "$in" : [ "01" ] } },
                {"details.thing": { "$in" : [ "01" ] } }
            ]
        }
    ]
}

我可以对对象中的第一级数组执行此操作，但我不确定如何对第二级数组执行此操作。

Answer 1

使用Array.prototype.filter:

const outputObject = {
  "startDate": {
    "$gte": "2017-03-29T00:00:00.000Z",
    "$lte": "2017-08-20T00:00:00.000Z"
  },
  "$and": [
    { 
      "$or": [
        {"details.thing": { "$in": [ "01" ] } },
        {"details.thing": { "$in": [ "01" ] } },
        {"details.thing": { "$in" : [ "01" ] } },
        {"details.thing": { "$in" : [ "01" ] } }
      ]
    },
    {
      "$or": []
    }
  ]
};

var filtered = outputObject.$and = outputObject.$and
  .filter(cond => cond.$or.length > 0)
;

// console.log('filtered', filtered);
// shows only the resulting array, your Object remains
// outputObject
console.log('outputObject', outputObject);