JavaScript 中循环 2 个数组无法正常工作

我有以下 JavaScript 代码，据我所知，该代码应该仅输出一次日期和相应的计算值。但是由于某种原因，我看到内部的输出不正确parseData日期记录两次并且值被覆盖的函数。我不确定是什么导致了这里的问题：这是可以使用 node.js 运行的完整要点 https://gist.github.com/anupdsouza/c2a79643743688af050d7d7b3c24f7eb

var express = require("express")
const NIFTY50_SYMBOL = 'NIFTY 50'
const NIFTYSMALLCAP250_SYMBOL = 'NIFTY SMLCAP 250'
const startDate = '02-Jan-2007'
const requestUrl = `https://www.niftyindices.com/Backpage.aspx/getTotalReturnIndexString`
const requestHeaders = {
  'Content-type': 'application/json; charset=UTF-8',
  'Accept-Language': 'en-GB',
  'Accept': '*/*'
}

const PORT = process.env.PORT || 3000

var app = express()
var path = require('path')
app.use(express.static(path.join(__dirname,"public")))

app.listen(PORT, () => {
  console.log("Server running on port " + PORT)
})

function getTodayAsString() {
  let today = new Date()
  let options = { day: '2-digit', month: 'short', year: 'numeric' }
  return today.toLocaleDateString('en-GB', options).replace(/ /g, '-')
}

async function fetchDataAsync(url, headers, body) {
  try {
    const response = await fetch(url, {
      method: 'POST',
      body: JSON.stringify(body),
      headers: headers,
    })
    const data = await response.json()
    return data
  } catch (error) {
    console.log('Error:', error)
  }
}

app.get("/", (req, res) => {
  const NIFTY50_REQ_BODY = {
    'name': NIFTY50_SYMBOL,
    'startDate': startDate,
    'endDate': '27-Mar-2023'//getTodayAsString()
  }

  const NIFTYSMALLCAP250_REQ_BODY = {
    'name': NIFTYSMALLCAP250_SYMBOL,
    'startDate': startDate,
    'endDate': '27-Mar-2023'//getTodayAsString()
  }

  const promise1 = fetchDataAsync(requestUrl, requestHeaders, NIFTY50_REQ_BODY)
  const promise2 = fetchDataAsync(requestUrl, requestHeaders, NIFTYSMALLCAP250_REQ_BODY)

  Promise.all([promise1, promise2])
  .then(([json1, json2]) => {
    parseData(json1.d, json2.d)
    res.send('Finished parsing data')
  })
  .catch(error => console.log('Error:', error))
})

const smallcapInitialTRI = parseFloat(2100.00)
const niftyInitialTRI = parseFloat(4807.77)

function parseData(niftyData, smallcapData) {
  const linebreak = "=".repeat(50);
  console.log(linebreak)
  console.log("Start parsing data:")
  console.log(linebreak)

  const niftyValues = JSON.parse(niftyData)
  const smallcapValues = JSON.parse(smallcapData)

  for(const smallcapObj of smallcapValues) {
    const smallcapDate = smallcapObj.Date
    const smallcapTRI = parseFloat(smallcapObj.TotalReturnsIndex)
    let niftyTRI = 0

    for (const niftyObj of niftyValues) {
      const niftyDate = niftyObj.Date

      if (niftyDate === smallcapDate) {
        niftyTRI = parseFloat(niftyObj.TotalReturnsIndex)
        console.log("date: "+ smallcapDate + " niftyTRI: " + niftyTRI + " smallcapTRI: " + smallcapTRI)
        break
      }
    }

    if (smallcapTRI && niftyTRI) {
      const relativeValue = ((smallcapTRI / smallcapInitialTRI) / (niftyTRI / niftyInitialTRI))
      console.log("date: "+ smallcapDate + " relative value: " + relativeValue)
    }
  }

  console.log(linebreak)
  console.log("Finished parsing data:")
  console.log(linebreak)
}

module.exports = app

输出有时会被错误地记录两次。我已在链接的要点评论中共享了整个输出。 可以找到 nifty_50_data 和 nifty_smallcap_data 的 JSON 响应here https://drive.google.com/file/d/1ELTi85mrxbN9eIpL524JJA_ESAxqV4U6/view?usp=sharing & here https://drive.google.com/file/d/1BJBGeor7KsRmbC4hqxGXYP6TsaOC_lxD/view?usp=sharing分别是因为回复太大而无法插入帖子中。

我尝试记录里面的值if (nifty_smallcap_tri && nifty_50_tri) {块，我看到奇怪的行为，同一日期发生了两次循环。我原以为它总是一次性的，因为我试图匹配内部 for 循环中的日期，考虑到日期只出现一次，理想情况下应该只发生一次：

Log 1:
date: 26 Mar 2010 nifty_smallcap_initial: 2100 nifty_50_initial: 4807.77
date: 26 Mar 2010 nifty_smallcap_tri: 2824.34 nifty_50_tri: 2824.34
date: 26 Mar 2010 relative value: 2.289414285714286

And

Log 2:
date: 26 Mar 2010 nifty_smallcap_initial: 2100 nifty_50_initial: 4807.77
date: 26 Mar 2010 nifty_smallcap_tri: 6562.47 nifty_50_tri: 2824.34
date: 26 Mar 2010 relative value: 5.3195481307390144

更奇怪的是日期26 Mar 2010json 响应中收到的 nifty_smallcap_tri 和 nifty_50_tri 值如下：

Server JSON response values:
{\"Index Name\":\"Nifty Smlcap 250\",\"Date\":\"26 Mar 2010\",\"TotalReturnsIndex\":\"2824.34\"}
{\"Index Name\":\"Nifty 50\",\"Date\":\"26 Mar 2010\",\"TotalReturnsIndex\":\"6562.47\"}

为什么日志1中都是nifty_smallcap_tri & nifty_50_tri的价值Nifty Smlcap 250从响应和日志 2 中为什么是nifty_smallcap_tri & nifty_50_tri响应中的值与实际值进行交换？

编辑： 我通过使用 JSON 响应作为字符串来验证 parseData 函数，它工作正常。下面是一个包含截断数据的工作示例，其中我使用 JSON 响应作为本地字符串调用该函数，并且运行良好。由于字符限制，无法发布整个数据转储。我不确定在对通过 api 获取的数据进行解析时导致问题的原因。

var result_list = []
var tri_data = {}
const nifty_smallcap_initial = 2100.00
const nifty_50_initial = 4807.77

const niftyJSON = "[{\"IndexName\":\"NIFTY50\",\"Date\":\"27Mar2020\",\"TotalReturnsIndex\":\"12193.62\"},{\"IndexName\":\"NIFTY50\",\"Date\":\"26Mar2020\",\"TotalReturnsIndex\":\"12167.15\"},{\"IndexName\":\"NIFTY50\",\"Date\":\"25Mar2020\",\"TotalReturnsIndex\":\"11710.71\"},{\"IndexName\":\"NIFTY50\",\"Date\":\"24Mar2020\",\"TotalReturnsIndex\":\"10983.15\"},{\"IndexName\":\"NIFTY50\",\"Date\":\"23Mar2020\",\"TotalReturnsIndex\":\"10710.41\"},{\"IndexName\":\"NIFTY50\",\"Date\":\"20Mar2020\",\"TotalReturnsIndex\":\"12298.74\"},{\"IndexName\":\"NIFTY50\",\"Date\":\"19Mar2020\",\"TotalReturnsIndex\":\"11620.92\"},{\"IndexName\":\"NIFTY50\",\"Date\":\"18Mar2020\",\"TotalReturnsIndex\":\"11904.02\"},{\"IndexName\":\"NIFTY50\",\"Date\":\"17Mar2020\",\"TotalReturnsIndex\":\"12604.41\"},{\"IndexName\":\"NIFTY50\",\"Date\":\"16Mar2020\",\"TotalReturnsIndex\":\"12928.18\"},{\"IndexName\":\"NIFTY50\",\"Date\":\"13Mar2020\",\"TotalReturnsIndex\":\"13987.31\"},{\"IndexName\":\"NIFTY50\",\"Date\":\"12Mar2020\",\"TotalReturnsIndex\":\"13474.38\"},{\"IndexName\":\"NIFTY50\",\"Date\":\"11Mar2020\",\"TotalReturnsIndex\":\"14694.31\"},{\"IndexName\":\"NIFTY50\",\"Date\":\"09Mar2020\",\"TotalReturnsIndex\":\"14684.56\"},{\"IndexName\":\"NIFTY50\",\"Date\":\"06Mar2020\",\"TotalReturnsIndex\":\"15440.48\"},{\"IndexName\":\"NIFTY50\",\"Date\":\"05Mar2020\",\"TotalReturnsIndex\":\"15833.21\"},{\"IndexName\":\"NIFTY50\",\"Date\":\"04Mar2020\",\"TotalReturnsIndex\":\"15805.53\"},{\"IndexName\":\"NIFTY50\",\"Date\":\"03Mar2020\",\"TotalReturnsIndex\":\"15878.98\"},{\"IndexName\":\"NIFTY50\",\"Date\":\"02Mar2020\",\"TotalReturnsIndex\":\"15632.14\"}]"

const smallcapJSON = "[{\"IndexName\":\"NiftySmlcap250\",\"Date\":\"27Mar2020\",\"TotalReturnsIndex\":\"3867.88\"},{\"IndexName\":\"NiftySmlcap250\",\"Date\":\"26Mar2020\",\"TotalReturnsIndex\":\"3834.21\"},{\"IndexName\":\"NiftySmlcap250\",\"Date\":\"25Mar2020\",\"TotalReturnsIndex\":\"3705.15\"},{\"IndexName\":\"NiftySmlcap250\",\"Date\":\"24Mar2020\",\"TotalReturnsIndex\":\"3614.88\"},{\"IndexName\":\"NiftySmlcap250\",\"Date\":\"23Mar2020\",\"TotalReturnsIndex\":\"3649.74\"},{\"IndexName\":\"NiftySmlcap250\",\"Date\":\"20Mar2020\",\"TotalReturnsIndex\":\"4164.75\"},{\"IndexName\":\"NiftySmlcap250\",\"Date\":\"19Mar2020\",\"TotalReturnsIndex\":\"4073.10\"},{\"IndexName\":\"NiftySmlcap250\",\"Date\":\"18Mar2020\",\"TotalReturnsIndex\":\"4293.66\"},{\"IndexName\":\"NiftySmlcap250\",\"Date\":\"17Mar2020\",\"TotalReturnsIndex\":\"4570.10\"},{\"IndexName\":\"NiftySmlcap250\",\"Date\":\"16Mar2020\",\"TotalReturnsIndex\":\"4677.61\"},{\"IndexName\":\"NiftySmlcap250\",\"Date\":\"13Mar2020\",\"TotalReturnsIndex\":\"4945.46\"},{\"IndexName\":\"NiftySmlcap250\",\"Date\":\"12Mar2020\",\"TotalReturnsIndex\":\"4911.61\"},{\"IndexName\":\"NiftySmlcap250\",\"Date\":\"11Mar2020\",\"TotalReturnsIndex\":\"5386.57\"},{\"IndexName\":\"NiftySmlcap250\",\"Date\":\"09Mar2020\",\"TotalReturnsIndex\":\"5400.60\"},{\"IndexName\":\"NiftySmlcap250\",\"Date\":\"06Mar2020\",\"TotalReturnsIndex\":\"5663.56\"},{\"IndexName\":\"NiftySmlcap250\",\"Date\":\"05Mar2020\",\"TotalReturnsIndex\":\"5795.22\"},{\"IndexName\":\"NiftySmlcap250\",\"Date\":\"04Mar2020\",\"TotalReturnsIndex\":\"5768.55\"},{\"IndexName\":\"NiftySmlcap250\",\"Date\":\"03Mar2020\",\"TotalReturnsIndex\":\"5859.40\"},{\"IndexName\":\"NiftySmlcap250\",\"Date\":\"02Mar2020\",\"TotalReturnsIndex\":\"5790.35\"}]"

function parseData(nifty_50_data, nifty_smallcap_data) {
  console.log("==============================================================")
  console.log("Start parsing data:")
  console.log("==============================================================")

  const niftySmallcapValues = JSON.parse(nifty_smallcap_data)
  const niftyFiftyValues = JSON.parse(nifty_50_data)

  for(const nifty_smallcap of niftySmallcapValues) {

    const date = nifty_smallcap.Date
    const nifty_smallcap_tri = parseFloat(nifty_smallcap.TotalReturnsIndex)
    let nifty_50_tri = 0

    for (const nifty_50 of niftyFiftyValues) {
      if (nifty_50.Date === nifty_smallcap.Date) {
        nifty_50_tri = parseFloat(nifty_50.TotalReturnsIndex)
        break
      }
    }

    if (nifty_smallcap_tri && nifty_50_tri) {
      const relative_value = ((nifty_smallcap_tri / nifty_smallcap_initial) / (nifty_50_tri / nifty_50_initial))
      console.log("date: "+ date + ", relative value: " + relative_value)

      tri_data['date'] = nifty_smallcap.Date
      tri_data['nifty_smallcap_tri'] = nifty_smallcap_tri
      tri_data['nifty_50_tri'] = nifty_50_tri
      tri_data['relative_value'] = relative_value

      result_list.push(tri_data)
    }
  }

  console.log("==============================================================")
  console.log("Finished parsing data:")
  console.log("==============================================================")
}

parseData(niftyJSON, smallcapJSON)

你的问题在于niftyindices.com

如果您尝试将其记录为

async function count() {
    const promise1 = fetchDataAsync(requestUrl, requestHeaders, NIFTY50_REQ_BODY);
    const promise2 = fetchDataAsync(requestUrl, requestHeaders, NIFTYSMALLCAP250_REQ_BODY, );
  const [json1,json2] = await Promise.all([promise1, promise2])
    
    const [niftyValues,smallcapValues] = [json1, json2].map(j=>JSON.parse(j.d))
    console.log({
        nifty: niftyValues.length,
        small: smallcapValues.length
    })
}
for (let i = 0; i < 30; i++) {
    await count()
}

你会发现它的结果是相当随机的

{ nifty: 4023, small: 4023 }
{ nifty: 5814, small: 8047 }
{ nifty: 8046, small: 12069 }
{ nifty: 4023, small: 12069 }
{ nifty: 12069, small: 9325 }
{ nifty: 12069, small: 8046 }
{ nifty: 4023, small: 8046 }
{ nifty: 8046, small: 4023 }
{ nifty: 4023, small: 8046 }
{ nifty: 4023, small: 8046 }
{ nifty: 4023, small: 8046 }
{ nifty: 4023, small: 8046 }
{ nifty: 12069, small: 8046 }
{ nifty: 8046, small: 4023 }
{ nifty: 8046, small: 4023 }
{ nifty: 4023, small: 8046 }
{ nifty: 8047, small: 12070 }
{ nifty: 4023, small: 6454 }

所以， 不Promise.all，按顺序等待每个人

    const json1 = await fetchDataAsync(requestUrl, requestHeaders, NIFTY50_REQ_BODY);
    const json2 = await fetchDataAsync(requestUrl, requestHeaders, NIFTYSMALLCAP250_REQ_BODY);
    parseData(json1, json2)

并检查数组长度是否正确（或者至少两个数组的长度相同）