字符串如何转为ArrayBuffer？

import { buffer } from '@kit.ArkTS';
/**
 * 字符串转ArrayBuffer
 * @param str
 * @returns
 */
static strToBuffer(src: string, encoding: buffer.BufferEncoding = 'utf-8'): ArrayBuffer {
  let buf = buffer.from(src, encoding);
  return buf.buffer
}