JavaScript - how to clear canvas?

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Created by:

Sujay

512

Simple solution:

// clear from x=0, y=0 on area width * height
context.clearRect(0, 0, canvas.width, canvas.height);

Using JavaScript it is possible to clear canvas in following way.

1. `clearRect` method example

// ONLINE-RUNNER:browser;

<!doctype html>
<html>
<head>
  <style>
    
    #my-canvas { border: 1px solid gray; }
    
  </style>
</head>
<body>
  <button onclick="drawCircle()">Draw circle!</button>
  <button onclick="clearCanvas()">Clear canvas!</button>
  <br /><br />
  <canvas id="my-canvas" width="300" height="300"></canvas>
  <script>

    var canvas = document.querySelector('#my-canvas');
    var context = canvas.getContext('2d');

    var xCenter = canvas.width / 2;
    var yCenter = canvas.height / 2;
    var circleRadius = 110;
    
    function drawCircle() {
        context.fillStyle = '#ff0000';
        context.beginPath();
        context.arc(xCenter, yCenter , circleRadius, 0, 2 * Math.PI);
        context.fill();
    }

    function clearCanvas() {
        context.clearRect(0, 0, canvas.width, canvas.height);
    }

    drawCircle();

  </script>
</body>
</html>