//用法
await img2base64("https://cdn-corner.resource.buzzbuzzenglish.com/qr-code.svg", 'anonymous');
//封装的方法
export const img2base64 = async (url, crossOrigin) => {
return new Promise(resolve => {
const img = new Image();
img.onload = () => {
const c = document.createElement('canvas');
c.width = img.naturalWidth;
c.height = img.naturalHeight;
const cxt = c.getContext('2d');
cxt.drawImage(img, 0, 0);
// 得到图片的base64编码数据
resolve(c.toDataURL('image/png'));
};
crossOrigin && img.setAttribute('crossOrigin', crossOrigin);
img.src = url;
});
};