Canvas-2D-Context-API-Primer/mouseposition.html at master · rroa/Canvas-2D-Context-API-Primer · GitHub

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<!--
To change this template use Tools | Templates.
-->
<!DOCTYPE html>
<html>
<head>
    <title>Mouse Position</title>
    <meta charset="utf-8" />
    <meta name="viewport" content="width=1024" />
    <meta name="apple-mobile-web-app-capable" content="yes" />
    <style type="text/css">
        canvas.default { border: 1px solid black; }
        textarea { border: 1px solid #888; width: 300px; height: 100px; }
    </style>
    <script>
        window.onload = function () {
          var canvas = document.getElementById('canvas');

          // Get a reference to the drawing context
          var ctx = canvas.getContext('2d');

          // Set the fill pattern
          ctx.fillStyle = 'gray';

          // Set the font
          ctx.font = "italic 200 36px/2 Unknown Font, sans-serif";

          ctx.fillText("Perform", 20, 40);
          ctx.fillText("mouse events", 20, 80);
          ctx.fillText("inside the canvas", 20, 120);

          function onMouseEvent (event) {
              var text = document.getElementById('feedback');
              text.value = 'x: ' + event.pageX + ' y: ' + event.pageY;
          }

          function onMouseEvent1 (event) {
              var text = document.getElementById('feedback1');
              var x, y;

              var offsetLeft = canvas.offsetLeft;
              var offsetTop = canvas.offsetTop;

              x = event.pageX;
              y = event.pageY;

              x -= offsetLeft;
              y -= offsetTop;
              text.value = 'x: ' + x + ' y: ' + y;
          }

          document.addEventListener('mousemove', onMouseEvent, false);
          canvas.addEventListener('mousemove', onMouseEvent1, false);
        };
    </script>
</head>
<body>
    <p>
      <a href="index.html">Back to index</a>
    </p>
    <canvas id="canvas" width="300" height="200" tabindex='0' class="default">
      This browser or document mode doesn't support canvas
    </canvas>
    <textarea id="feedback"></textarea>
    <textarea id="feedback1"></textarea>
</body>
</html>