SOURCE

console 命令行工具 X clear

                    
>
console
window.onload=function(){
        var canvas = document.getElementById("canvas");
        var ctx = canvas.getContext("2d");
        this.width = canvas.width;
        this.height = canvas.height;
        ctx.beginPath();
        ctx.moveTo(90, 50);
        ctx.quadraticCurveTo(190, 0, 300, 10);
        ctx.lineWidth=15;
        var gnt1 = ctx.createLinearGradient(0,0,400,300);
        gnt1.addColorStop(0.5,'rgba(3,131,254, 0)');
        gnt1.addColorStop(0,'rgba(3,131,254, 1)');
        gnt1.addColorStop(1,'rgba(3,131,254, 1)');
        ctx.strokeStyle = gnt1;
        ctx.lineCap='round';
        ctx.stroke();
        ctx.closePath();


    }

canvas = document.getElementById("canvas");
ctx = canvas.getContext("2d")
ctx.lineWidth = 2;
ctx.strokeStyle = "#B7E0FF";
ctx.beginPath();
ctx.setLineDash([2, 9]);
ctx.moveTo(35, 76);
ctx.quadraticCurveTo(260, 99, 323, 255);
ctx.lineCap='round';
ctx.stroke();
<html>
    <head></head>
<body>
	<canvas id="canvas" width="400" height="300"></canvas>
</body>
</html>
#canvas{
    background: rgb(241, 217, 217);
}