export function base64src(base64data, cb) {
  const [, format, bodyData] = /data:image\/(\w+);base64,(.*)/.exec(base64data) || [];
  if (!format) {
    return (new Error('ERROR_BASE64SRC_PARSE'));
  }
  const filePath = `${wx.env.USER_DATA_PATH}/${FILE_BASE_NAME}.${format}`;

  // 这里的buffer为 undefined
  const buffer = uni.base64ToArrayBuffer(bodyData);

  console.log("buffer.byteLength===")
  console.log(buffer.byteLength)
  fsm.writeFile({
    filePath,
    data: buffer,
    encoding: 'binary',
    success() {
		console.log("单页模式保存成功==")
		console.log(filePath)
      cb(filePath);
    },
    fail(error) {
		console.log("单页模式保存报错==")
		console.log(error)
      return (new Error('ERROR_BASE64SRC_WRITE'));
    },
  });
};