Chart.js - 未捕获的参考错误：未定义图表

Question

I'm using chart.js and here is my code.

<script scr="https://cdnjs.cloudflare.com/ajax/libs/Chart.js/2.9.3/Chart.min.js"></script>

var mychart = document.getElementById("myPieChart").getContext('2d');
let round_graph = new chart(mychart, {
type:'doughnut',
data:{
  labels:['Billed Samples (Today)','Collected Samples (Today)','Completed Test (Today)','Pending For Validation'],
  datasets:[{
    lable:'Samples',
    data :[
      document.getElementById('billed_sample_today').innerHTML,
      document.getElementById('bleeded_sample_today').innerHTML,
      document.getElementById('completed_sample_today').innerHTML,
      document.getElementById('pending_sample_today').innerHTML
    ],
    backgroundColor: ['#4e73df', '#1cc88a', '#36b9cc'],
      hoverBackgroundColor: ['#2e59d9', '#17a673', '#2c9faf'],
      hoverBorderColor: "rgba(234, 236, 244, 1)",
  }]
}

})

I'm getting the Uncaught ReferenceError: chart is not defined error on console. How can i correct this?

Answer 1

There are two things that are wrong:

1. classes should have a capital letter. new chart(mychart, { -> new Chart

2. The library from the CDN doesn't seem to return Chart. Try the one they recommend in their documentation: https://www.chartjs.org/docs/latest/getting-started/

Here is a working example:

 <div id="billed_sample_today">1</div> <div id="bleeded_sample_today">2</div> <div id="completed_sample_today">3</div> <div id="pending_sample_today">4</div> <canvas id="myPieChart"></canvas> <script src="https://cdn.jsdelivr.net/npm/chart.js@2.9.3"></script> <script> var mychart = document.getElementById("myPieChart").getContext('2d'); let round_graph = new Chart(mychart, { type: 'doughnut', data: { labels: ['Billed Samples (Today)', 'Collected Samples (Today)', 'Completed Test (Today)', 'Pending For Validation'], datasets: [{ lable: 'Samples', data: [ document.getElementById('billed_sample_today').innerHTML, document.getElementById('bleeded_sample_today').innerHTML, document.getElementById('completed_sample_today').innerHTML, document.getElementById('pending_sample_today').innerHTML ], backgroundColor: ['#4e73df', '#1cc88a', '#36b9cc'], hoverBackgroundColor: ['#2e59d9', '#17a673', '#2c9faf'], hoverBorderColor: "rgba(234, 236, 244, 1)", }] } }) </script>

Answer 2

There is issue with version 2.9.3 . Version 2.7.3 is working.

Same time you have to call new Chart not new chart

 window.onload = () => { var mychart = document.getElementById("myPieChart").getContext('2d'); let round_graph = new Chart(mychart, { type:'doughnut', data:{ labels:['Billed Samples (Today)','Collected Samples (Today)','Completed Test (Today)','Pending For Validation'], datasets:[{ lable:'Samples', data:[ document.getElementById('billed_sample_today').innerHTML, document.getElementById('bleeded_sample_today').innerHTML, document.getElementById('completed_sample_today').innerHTML, document.getElementById('pending_sample_today').innerHTML ], backgroundColor: ['#4e73df', '#1cc88a', '#36b9cc'], hoverBackgroundColor: ['#2e59d9', '#17a673', '#2c9faf'], hoverBorderColor: "rgba(234, 236, 244, 1)", }] } }) }

 <script type="text/javascript" src="https://cdnjs.cloudflare.com/ajax/libs/Chart.js/2.7.3/Chart.min.js"></script> <canvas id="myPieChart" ></canvas>