javascript - 计算 Json 数组中项目的大小

Question

我正在构建一个 JSON 响应，如下所示:

{
  "G5LDUHRPEEA6B-39CFBWYA": [],
  "JMSK0DKOEEA0UXMY750O3W": [],
  "ISVN8JF1EEAD3W398ZNOSA": [
    {

      "delloData": "1478644629",
      "ref": "75",
      "dataType": "String",
      "somePart": LA,
      "hello": "OUTSIDE"

    },
    {

      "delloData": "1478644629",
      "ref": "75",
      "dataType": "String",
      "somePart": Chicago,
      "hello": “Inside"
    },
    {

      "delloData": "1478644629",
      "ref": "75",
      "dataType": "String",
      "somePart": Austin,
      "hello": “Inside"
    }
  ],
  "VRG0IJF1EEAD3W398ZNOSA": [{

      "delloData": "1478644629",
      "ref": "75",
      "dataType": "String",
      "somePart": Chicago,
      "hello": “Inside"
    },
    {

      "delloData": "1478644629",
      "ref": "75",
      "dataType": "String",
      "somePart": Austin,
      "hello": “Inside"
    }],
  "OGAESJF2EEAD3W398ZNOSA": [],
  "SC9OMJF2EEAD3W398ZNOSA": []
  }

我想计算数组中的项目总数，包括内部数组，并忽略内部数组是否为空，如“SC9OMJF2EEAD3W398ZNOSA”:[] 我尝试了 _.size(collection) 但我需要知道如何删除空的内部尺寸。提前致谢

Answer 1

您可以使用 Array.prototype.reduce 并循环来总结数组的长度 - 请参阅下面的演示:

var object={"G5LDUHRPEEA6B-39CFBWYA":[],"JMSK0DKOEEA0UXMY750O3W":[],"ISVN8JF1EEAD3W398ZNOSA":[{"delloData":"1478644629","ref":"75","dataType":"String","somePart":"LA","hello":"OUTSIDE"},{"delloData":"1478644629","ref":"75","dataType":"String","somePart":"Chicago","hello":"Inside"},{"delloData":"1478644629","ref":"75","dataType":"String","somePart":"Austin","hello":"Inside"}],"VRG0IJF1EEAD3W398ZNOSA":[{"delloData":"1478644629","ref":"75","dataType":"String","somePart":"Chicago","hello":"Inside"},{"delloData":"1478644629","ref":"75","dataType":"String","somePart":"Austin","hello":"Inside"}],"OGAESJF2EEAD3W398ZNOSA":[],"SC9OMJF2EEAD3W398ZNOSA":[]}

var result = Object.keys(object).reduce(function(p,c){
  p+= object[c].length;
  return p;
},0);


console.log(result);