canvas获取鼠标位置
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<meta http-equiv="X-UA-Compatible" content="ie=edge">
<title>Document</title>
<style>
canvas{ border: 1px solid black; }
</style>
</head>
<body>
<canvas id="myCanvas" width="500" height="500"></canvas>
<script>
var canvas = document.getElementById("myCanvas");
var ctx = canvas.getContext("2d");
ctx.font = "16px Arial";
canvas.addEventListener("mousemove", function(e) {
var cRect = canvas.getBoundingClientRect();
var canvasX = Math.round(e.clientX - cRect.left);
var canvasY = Math.round(e.clientY - cRect.top);
ctx.clearRect(0, 0, canvas.width, canvas.height);
ctx.fillText("X: "+canvasX+", Y: "+canvasY, 10, 20);
});
</script>
</body>
</html>
