this question is that I don't know enough about iframe before the card owner thinks that it is ridiculous to keep looking for answers in react.
the iframe introduced is local so that we can think differently. We get the designated elements that are highly directly assigned to react in the sub-iframe.

1. We need to introduce react-dom into the parent page, which is the react page, to bind the dom element of the page

like this

import ReactDOM from 'react-dom';
<iframe 
    id="iframe-b"
    style={{width:'100%'}}
    onLoad={() => {}} 
    ref="iframe" 
    src={inkSrc}
    width="100%" 
    scrolling="yes" 
    frameBorder="0"
      >
</iframe> 

2. After the child page is fully loaded, use js to get the page height to the parent react page
like this

  let h  =  document.getElementById('iframe-body').scrollHeight;
  parent.document.getElementById("iframe-b").style.height = h + "px"; 

accesses the dom attribute of the child page on the parent page, which is restricted by the same origin policy and is only applicable to certain scenarios. A more general approach is to listen to window.onload, in the child page to get its own page dom height, and then pass the message to the parent page through postMessage. The parent page gets the dom height of the child page by listening for message events, thus setting the iframe element height.