如何将一个字符串转换为Base64字符串？

import { util } from '@kit.ArkTS';
/**
 * 字符串转Base64字符串
 * @param src 字符串
 * @returns
 */
static strToBase64(src: string): string {
  let textEncoder = new util.TextEncoder('utf-8');
  let uint8Array = textEncoder.encodeInto(src);
  let result = Base64Util.encodeToStrSync(uint8Array);
  return result;
}