Question

当前我正在尝试学习Javascript，但是我似乎无法解决此问题：

我有一个填充数据的Json文件。我想要八月的第一个月的特定数组（报告，平均值，全局），并将它们（通过变量）插入到我的图表中。所以我得到一个图表：

八月

报告：7
平均水平：25
全局：20

6月...等。

欢迎任何帮助或提示！

JSON数据

[{
    "month": "August",
    "reports": 7,
    "average": 25,
    "global": 20,
    "percentage": 14
}, {
    "month": "July",
    "reports": 22,
    "average": 25,
    "global": 20,
    "percentage": 44
}, {
    "month": "June",
    "reports": 12,
    "average": 25,
    "global": 20,
    "percentage": 24
}]

JS代码

window.onload = function() {

    var reports = [];

    $.getJSON("data.json", function(data) {
        reports = data;
    });


    var repaug = 7;
    var avg = 25;
    var global = 20;

    var ctx = document.getElementById("Chart1");
    var Chart1 = new Chart(ctx, {
        type: 'doughnut',
        data: {
            labels: ["Reports", "Average PSN", "Global Average"],
            datasets: [{
                label: '# of reports',
                data: [repaug, global, avg],
                backgroundColor: [
                    'rgba(255, 99, 132, 0.2)',
                    'rgba(54, 162, 235, 0.2)',
                    'rgba(255, 206, 86, 0.2)',
                    'rgba(75, 192, 192, 0.2)',
                    'rgba(153, 102, 255, 0.2)',
                    'rgba(255, 159, 64, 0.2)'
                ],
                borderColor: [
                    'rgba(255,99,132,1)',
                    'rgba(54, 162, 235, 1)',
                    'rgba(255, 206, 86, 1)',
                    'rgba(75, 192, 192, 1)',
                    'rgba(153, 102, 255, 1)',
                    'rgba(255, 159, 64, 1)'
                ],
                borderWidth: 1
            }]
        },
        options: {}
    })
}

Answer 1

您可以在datasets内添加一个数组，因此首先需要循环进行响应。

您可以对数组使用map()方法。

演示

let arrayData =[{"month":"August","reports":7,"average":25,"global":20,"percentage":14},{"month":"July","reports":22,"average":25,"global":20,"percentage":44},{"month":"June","reports":12,"average":25,"global":20,"percentage":24}],
    datasets = arrayData.map(item => {
        return {
            label: `${item.month}`,
            data: [item.reports, item.average, item.global],
            backgroundColor: [
                'rgba(255, 99, 132, 0.2)',
                'rgba(54, 162, 235, 0.2)',
                'rgba(255, 206, 86, 0.2)',
                'rgba(75, 192, 192, 0.2)',
                'rgba(153, 102, 255, 0.2)',
                'rgba(255, 159, 64, 0.2)'
            ],
            borderColor: [
                'rgba(255,99,132,1)',
                'rgba(54, 162, 235, 1)',
                'rgba(255, 206, 86, 1)',
                'rgba(75, 192, 192, 1)',
                'rgba(153, 102, 255, 1)',
                'rgba(255, 159, 64, 1)'
            ],
            borderWidth: 1
        }
    }),
    ctx = document.getElementById("myChart").getContext('2d');

new Chart(ctx, {
    type: 'doughnut',
    data: {
        labels: ["Reports", "Average PSN", "Global Average"],
        datasets: datasets
    },
    options: {
        responsive: true,
        legend: {
            position: 'top',
        },
        animation: {
            animateScale: true,
            animateRotate: true
        },
        tooltips: {
            callbacks: {
                label: function(item, data) {
                    let datasets = data.datasets,
                        dIndex = item.datasetIndex,
                        index = item.index;
                  
                    return `${datasets[dIndex].label} : ${data.labels[index]} : ${datasets[dIndex].data[index]}`;
                }
            }
        }
    }
});

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/Chart.js/2.7.2/Chart.bundle.min.js"></script>
<canvas id="myChart"></canvas>

用特定的JSON数组填充Chart.js

1 个答案: