javascript - 如何在chartjs上实现动态数据？

Question

我需要你的帮助来学习如何动态地将数据从 json 文件实现到 Chartjs。我需要动态填充的字段是labels 和data。

JSON File <<<

[
   {
      "EFICAZ_TAB_ITEM_ID":1,
      "EFICAZ_PERCENTS":99
   },
   {
      "EFICAZ_TAB_ITEM_ID":2,
      "EFICAZ_PERCENTS":99
   },
   {
      "EFICAZ_TAB_ITEM_ID":3,
      "EFICAZ_PERCENTS":99
   }
]


CHARTJS <<<

var ctx = document.getElementById('myChart').getContext('2d');
var chart = new Chart(ctx, {
    // The type of chart we want to create
    type: 'line',

    // The data for our dataset
    data: {
        labels: [???],
        datasets: [{
            label: "My First dataset",
            backgroundColor: 'rgb(255, 99, 132)',
            borderColor: 'rgb(255, 99, 132)',
            data: [???],
        }]
    },

    // Configuration options go here
    options: {}
});

Answer 1

我使用 $.ajax() 来获取 JSON 数据，并将数据保存在两个数组中，然后您可以将这些数组用于图表标签和数据。希望这有帮助!

 var lbl = [];
    var dta = [];

    $.ajax({
      url: "test.json",
      dataType: 'json',
      async: false,
      success: function(data) {
        $.each(data, function(i, field){
             lbl.push(field.EFICAZ_TAB_ITEM_ID
    );
               dta.push(field.EFICAZ_PERCENTS);

           });
      }
    });


     $.getJSON("test.json", function(result){
           $.each(result, function(i, field){
             lbl.push(field.EFICAZ_TAB_ITEM_ID
    );
               dta.push(field.EFICAZ_PERCENTS);

           });
        });


    var ctx = document.getElementById("myCanvas").getContext('2d');



    var chart = new Chart(ctx, {
        // The type of chart we want to create
        type: 'line',

        // The data for our dataset
        data: {
            labels: lbl,
            datasets: [{
                label: "My First dataset",
                backgroundColor: 'rgb(255, 99, 132)',
                borderColor: 'rgb(255, 99, 132)',
                data: dta,
            }]
        },

        // Configuration options go here
        options: {}
    });