console 命令行工具 X clear

console

window.onload = function(){
    var canvas = document.getElementById('myCanvas');
    var ct = canvas.getContext('2d');

    function resizeCanvas(){
        canvas.width = window.innerWidth
        canvas.height = window.innerHeight
    }

    function clearCanvas(){
        ct.fillStyle = "#fff";
        ct.fillRect(0,0,canvas.width,canvas.height)
    }

    window.addEventListener('resize',resizeCanvas,false)
    resizeCanvas()
}

<canvas id="myCanvas" width="600" height="600">浏览器不支持</canvas>vas>