chart.js柱状图

<canvas id="popChart" width="600" height="400"></canvas>
<script>
	var ctx = $("#popChart");
	var ctx = document.getElementById("popChart");
	var ctx = document.getElementById("popChart").getContext("2d");
	let labels = ['3月', '4月', '5月', '6月', '7月'];
	let data = [99, 80, 99, 99, 99]
	var barChart = new Chart(ctx, {
		type: 'bar',
		data: {
			labels: labels,
			datasets: [{
				label: 'BMI',
				data: data,
				backgroundColor: [
					'rgba(255, 99, 132, 0.6)',
					'rgba(54, 162, 235, 0.6)',
					'rgba(255, 206, 86, 0.6)',
					'rgba(75, 192, 192, 0.6)',
					'rgba(153, 102, 255, 0.6)',
					'rgba(255, 159, 64, 0.6)',
					'rgba(255, 99, 132, 0.6)',
					'rgba(54, 162, 235, 0.6)',
					'rgba(255, 206, 86, 0.6)',
					'rgba(75, 192, 192, 0.6)',
					'rgba(153, 102, 255, 0.6)'
				]
			}]

		},
		options: {
			legend: {
				//除去label
				display: false,
			},
			scales: {
				yAxes: [{
					ticks: {
						//y从零开始
						beginAtZero: true
					}
				}]
			},
			//显示具体数值
			"animation": {
				"duration": 1,
				"onComplete": function() {
					var chartInstance = this.chart,
						ctx = chartInstance.ctx;

					ctx.font = Chart.helpers.fontString(Chart.defaults.global.defaultFontSize, Chart.defaults.global.defaultFontStyle, Chart.defaults.global.defaultFontFamily);
					ctx.textAlign = 'center';
					ctx.textBaseline = 'bottom';

					this.data.datasets.forEach(function(dataset, i) {
						var meta = chartInstance.controller.getDatasetMeta(i);
						meta.data.forEach(function(bar, index) {
							var data = dataset.data[index];
							ctx.fillText(data, bar._model.x, bar._model.y - 5);
						});
					});
				}
			},

		}
	});
</script>