var elements = document.querySelectorAll("button")
for (let i = 0; i < 3; i ++){
elements[i].counter = 0
elements[i].addEventListener("click", function(){
this.counter++
this.innerHTML = this.counter
})
}<!DOCTYPE HTML>
<html>
<head>
<script type="text/javascript">
window.onload = function () {
var chart = new CanvasJS.Chart("chartContainer", {
theme: "light1", // "light2", "dark1", "dark2"
animationEnabled: false, // change to true
title:{
text: "Basic Column Chart"
},
data: [
{
// Change type to "bar", "area", "spline", "pie",etc.
type: "column",
dataPoints: [
{ label: "apple", y: 10 },
{ label: "orange", y: 15 },
{ label: "banana", y: 25 },
{ label: "mango", y: 30 },
{ label: "grape", y: 28 }
]
}
]
});
chart.render();
}
</script>
</head>
<body>
<div id="chartContainer" style="height: 370px; width: 100%;"></div>
<script src="https://canvasjs.com/assets/script/canvasjs.min.js"> </script>
</body>
</html>