javascript - 如何将来自外部源的时间作为 X 轴添加到 ChartJS 图表中？

Question

https://plnkr.co/edit/O4BxVsdOZBc4R68p

fetch(target)
  .then(response => response.json())
  .then(data => {
    var prices = data['Time Series (5min)'];
    for (prop in prices) {
      var stockPrices = prices[prop]['1. open'];
      //change to 2. high, etc
      console.log(`${prop} : ${stockPrices}`);
      stocksData.datasets[0].data.push({x: prop, y: +stockPrices})
      //time x axes are preventing render
      window.lineChart.update();
    }
  })

我正在从 AlphaVantage API 获取信息，并尝试将时间绘制为 X 轴，将开盘价绘制为 Y 轴。然而，来自 API 的时间格式很奇怪，并且没有显示为图表。我研究过 Moment.js，但这似乎是在浪费时间，而不是格式化它们。谁能给我一些有关正确绘制时间的指示？

Answer 1

您的问题来自两件事:

1. 您的图表配置中带有 xAxes 的选项应改为 xAxis
2. 图表数据中缺少标签且数据正确

以下是有效的代码:

var stocksData = {
  datasets: [
    {
      label: 'open',
      backgroundColor: 'rgba(104,0,255,0.1)',
      data: [

      ],
    },
  ],
};
window.onload = function() {
  var ctx = document.getElementById('myChart').getContext('2d');

  var lineChart = new Chart(ctx, {
    type: 'line',
    data: stocksData,
    options: {
      scales: {
        xAxis: [
          {
            type: 'linear',
            position: 'bottom',
          },
        ],
      },
    },
  });
  window.lineChart = lineChart;
};

var sym = 'AAPL'; //get from form
var tseries = 'TIME_SERIES_INTRADAY'; //get from form
var target = `https://www.alphavantage.co/query?function=${tseries}&symbol=${sym}&interval=5min&apikey=VA3RZ8B9PPYWKQKN`;
function update () {
fetch(target)
  .then(response => response.json())
  .then(data => {
    var prices = data['Time Series (5min)'];
    for (prop in prices) {
      var stockPrices = prices[prop]['1. open'];
      //change to 2. high, etc
      console.log(`${prop} : ${stockPrices}`);
      //stocksData.datasets[0].data.push({x: prop, y: +stockPrices})
      stocksData.datasets[0].data.push(stockPrices);
      // Format date here. For example with Moment:
      // var date = moment(prop).format('YYYY-MM-DD')
      stocksData.labels.push(prop);
      //time x axes are preventing render
      window.lineChart.update();
    }
  })
  .catch(error => console.error(error));
}

图表数据的完整格式如下:

var stocksData = {
  labels: ['date1', 'date2', 'date3', 'date4'],
  datasets: [
    {
      label: 'open',
      backgroundColor: 'rgba(104,0,255,0.1)',
      data: [
        'data1', 'data2', 'data3', 'data4'
      ],
    },
  ],
};

然后每个数据和日期标签应该分别推送:

stocksData.datasets[0].data.push(stockPrices);
stocksData.labels.push(prop);

要使用 Moment 进行格式化，您可以使用:

var dateStr = moment(prop).format('YYYY-MM-DD');