/**
 * @param {String} text 把输入的文字转化为base64的img图片
 */
export default function (text, width = 100, height = 50) {
  const canvas = document.createElement("canvas");
  canvas.width = width;
  canvas.height = height;
  const ctx = canvas.getContext("2d");
  ctx.fillStyle = "white";
  ctx.fillRect(0, 0, width, height);
  ctx.fillStyle = "black";
  ctx.font = "30px serif";
  ctx.fillText(text, 0, 30);
  return canvas.toDataURL();
}