Question

这里我有这样的数据，

var dataArray = '[{"name":"books","value":43},{"name":"DVDs","value":99},{"name":"Magazines","value":37},{"name":"eBooks","value":88},{"name":"Other awesome things","value":67}]';

我想动态地使用此数据构建此chart，这意味着我的json在实际项目中会很大，来自database。

这里是我想要的chart的jsfiddle（动态地为我的情况）：http://jsfiddle.net/artefactory/m4on9L4p/

＆＃13;

//canvasJS example - doughnut chart showing collection breakdown.   

var dataArray = '[{"name":"books","value":43},{"name":"DVDs","value":99},{"name":"Magazines","value":37},{"name":"eBooks","value":88},{"name":"Other awesome things","value":67}]';

window.onload = function () {
    var chart = new CanvasJS.Chart("chartContainer",
    {
      title:{
        text: "What's in our collection"
      },
      data: [
      {
       type: "doughnut",
        // how to substitute above array here
       dataPoints: [
       {  y: 53.37, indexLabel: "Books" },
       {  y: 35.0, indexLabel: "DVDs" },
       {  y: 7, indexLabel: "Magazines" },
       {  y: 2, indexLabel: "eBooks" },
       {  y: 5, indexLabel: "Other awesome things" }
       ]
     }
     ]
   });

    chart.render();
  }

＆＃13;

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<script src="http://cdnjs.cloudflare.com/ajax/libs/canvasjs/1.4.1/canvas.min.js"></script>
 <div id="chartContainer" style="height: 300px; width: 100%;">  </div>

＆＃13;

我想建立这个

dataPoints: [
           {  y: 53.37, indexLabel: "Books" },
           {  y: 35.0, indexLabel: "DVDs" },
           {  y: 7, indexLabel: "Magazines" },
           {  y: 2, indexLabel: "eBooks" },
           {  y: 5, indexLabel: "Other awesome things" }
           ]

动态地使用我的json。我怎么能这样做？

问题而不是使用hardcoded值，我想使用json来构建图表？

Answer 1

使用JSON.parse()和Array.prototype.map()函数的解决方案：

...
dataPoints:  JSON.parse(dataArray).map(function (o) {
    return {y: o.value, indexLabel: o.name};
})
...

Answer 2

值53.37,35.0是如何得出的？是否有推导的数学公式？

如果你只是将“names”映射到indexLabel而将“value”映射到x，那么这段代码应该可以工作。

var desiredObj = x.map(function(currentElement) {return {x: currentElement.value, indexLabel: currentElement.name}});

Answer 3

你可以像这样使用jQuery maop函数：

var myNewDataArray = $.map(dataArray,function(a,b){
    return {
        y : a.value,
        indexLabel : a.name
    }
});

如何将数据传递到对象数组中

3 个答案: