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| const pixel = (canvas, image, scale)=> { scale *= 0.01; canvas.width = image.width; canvas.height = image.height;
let scaledW = canvas.width * scale; let scaledH = canvas.height * scale;
let ctx = canvas.getContext('2d'); ctx.imageSmoothingEnabled = false; ctx.mozImageSmoothingEnabled = false; ctx.webkitImageSmoothingEnabled = false; ctx.msImageSmoothingEnabled = false;
ctx.drawImage(image, 0, 0, scaledW, scaledH); ctx.drawImage(canvas, 0, 0, scaledW, scaledH, 0, 0, canvas.width, canvas.height); };
btn.addEventListener('click', function(){ const Regex = new RegExp(/^100$|^(\d|[1-9]\d)(\.\d+)*$/) let scale = input.value; if(scale==''){ scale = 40; } if(!Regex.test(scale)){ window.alert('输入不规范') return; } console.log(scale); pixel(canvas,img,scale); }, false);
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