day30/20.html at main · githubber-me/day30 · GitHub

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<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Simple Drawing App</title>
</head>
<body>
    <h1>Simple Drawing App</h1>
    <canvas id="canvas" width="500" height="500" style="border:1px solid #000000;"></canvas>

    <script>
        const canvas = document.getElementById('canvas');
        const context = canvas.getContext('2d');
        let isDrawing = false;

        function startDrawing(event) {
            isDrawing = true;
            context.beginPath();
            context.moveTo(event.clientX - canvas.offsetLeft, event.clientY - canvas.offsetTop);
        }

        function continueDrawing(event) {
            if (isDrawing) {
                context.lineTo(event.clientX - canvas.offsetLeft, event.clientY - canvas.offsetTop);
                context.stroke();
            }
        }

        function stopDrawing() {
            isDrawing = false;
            context.closePath();
        }

        canvas.addEventListener('mousedown', startDrawing);
        canvas.addEventListener('mousemove', continueDrawing);
        canvas.addEventListener('mouseup', stopDrawing);
        canvas.addEventListener('mouseleave', stopDrawing);
    </script>
</body>
</html>