使用例
html
<portal to="destination">
<p>This slot content will be rendered wherever the
<portal-target> with name 'destination'
is located.
</p>
</portal>
<portal-target name="destination">
<!--
This component can be located anywhere in your App
(i.e. right before the </body> tag, good for overlays).
The slot content of the above portal component will be rendered here.
-->
</portal-target>