Nodejs base64转存为图片

替换 base64头，writeFile 指定编码为 base64

var content = "data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAOYAAA......"

const ext = content.match(/^data:image\/(\w+)\+?\w*;base64,/);

const imgPath = 'tempimg.' + ext[1]

fs.writeFileSync(imgPath, content.replace(/^data:image\/\w+;base64,/, ""), "base64");