ChartsJS获取工具提示的数据/数据集标签的值

// 创建图表
var myChart = new Chart(ctx, {
  type: 'bar',
  data: data,
  options: {
    tooltips: {
      callbacks: {
        label: function(tooltipItem, data) {
          // 获取数据集标签的值
          var datasetLabel = data.datasets[tooltipItem.datasetIndex].label || '';

          // 获取工具提示的数据的值
          var value = tooltipItem.yLabel;

          return datasetLabel + ': ' + value;
        }
      }
    }
  }
});

// 监听事件
myChart.canvas.addEventListener('mousemove', function(e) {
  var activePoints = myChart.getElementsAtEventForMode(e, 'nearest', { intersect: true });

  if (activePoints.length > 0) {
    var firstPoint = activePoints[0];
    var datasetIndex = firstPoint.datasetIndex;
    var index = firstPoint.index;

    // 获取工具提示的数据的值
    var value = myChart.data.datasets[datasetIndex].data[index];

    // 获取数据集标签的值
    var datasetLabel = myChart.data.datasets[datasetIndex].label || '';

    console.log(datasetLabel + ': ' + value);
  }
});