Vue composition API 实现一键复制

<input
  type="text"
  ...
  onfocus="this.select()"
  ref="inputLink"
>

...
const inputLink = ref({} as unknown);
...
const copyLink = () => {
  (inputLink.value as HTMLInputElement).select();
  document.execCommand("copy");
  alert("复制成功");
}