canvas签名 

<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>

<body>
    <canvas id="canvas" width="600" height="600">
        你的浏览器不支持canvas，请更新浏览器或者换一个浏览器
    </canvas>
</body>
<script>
    const canvas = document.querySelector("#canvas");
    canvas.style.backgroundColor = "orange"
    const ctx = canvas.getContext("2d");
    canvas.addEventListener('mouseenter', () => {
        console.log("鼠标进来了");
        canvas.addEventListener('mousedown', (zhou) => {
            console.log("鼠标按下了");
            ctx.beginPath()
            ctx.moveTo(zhou.offsetX, zhou.offsetY)
            canvas.addEventListener('mousemove', draw)
        })
        canvas.addEventListener('mouseup', () => {
            console.log("鼠标抬起了");
            canvas.removeEventListener('mousemove', draw)
        })
    })
    function draw(event) {
        ctx.lineTo(event.offsetX, event.offsetY)
        ctx.stroke()
    }
</script>

</html>
posted @ 2021-11-24 11:35  走我们钓鱼去  阅读(56)  评论(0)    收藏  举报