EN
JavaScript - how to clear canvas?
12 points
Simple solution:
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// clear from x=0, y=0 on area width * height
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context.clearRect(0, 0, canvas.width, canvas.height);
Using JavaScript it is possible to clear canvas in following way.
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<html>
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<head>
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<style>
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#my-canvas { border: 1px solid gray; }
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</style>
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</head>
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<body>
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<button onclick="drawCircle()">Draw circle!</button>
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<button onclick="clearCanvas()">Clear canvas!</button>
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<br /><br />
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<canvas id="my-canvas" width="300" height="300"></canvas>
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<script>
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var canvas = document.querySelector('#my-canvas');
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var context = canvas.getContext('2d');
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var xCenter = canvas.width / 2;
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var yCenter = canvas.height / 2;
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var circleRadius = 110;
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function drawCircle() {
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context.fillStyle = '#ff0000';
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context.beginPath();
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context.arc(xCenter, yCenter , circleRadius, 0, 2 * Math.PI);
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context.fill();
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}
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function clearCanvas() {
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context.clearRect(0, 0, canvas.width, canvas.height);
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}
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drawCircle();
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</script>
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</body>
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</html>