javascript - 更改数据时，为什么每次按下按钮数据都会减少？

Question

这是一个显示问题的jsfiddle:https://jsfiddle.net/ost6g8hb/1/

按钮可以改变数据，但为什么每次按下按钮都会丢失第一个数据？

 function categoriesIntoSeries(data) {
    rows = data.series[0].data;
    data.series = [];
     for (i = 0; i < rows.length; i++) {
     cat = rows[i].category;
     catExists = false;
      for (j = 0; j < data.series.length; j++) {
        if (data.series[j].name == cat) {
          // Add a data point to existing series
          data.series[j].data.push(rows[i]);
          catExists = true;
        }
      }
      if (!catExists) {
        // When category is encountered for the first time, create a series
       data.series.push({name: cat, data: [rows[i]]})
       }
    }

  };



$('#EU28').click(function () {
     chart.update({
     data: {
            seriesMapping: [{category: 0, y: 2}],
            },
            title: {
      text: 'EU28' },
    });
});

Answer 1

您需要禁用firstRowAsNames数据属性:

chart.update({
    data: {
        firstRowAsNames: false,
        seriesMapping: [{...}],
    },
    ...
});

现场演示: https://jsfiddle.net/BlackLabel/6dq42rtj/

API引用: https://api.highcharts.com/highcharts/data.firstRowAsNames