React.js dangerouslySetInnerHTML 导致 [object Error] {}

Question

I'm using React. I have a string variable in state containing HTML text. This text changes, so I need to be able to insert it into my page and have it appear as rendered HTML, not just a string of text. While I've found some third-party work-arounds, it seems the most direct option is to use the dangerouslySetInnerHTML property. but when I do this, the whole page disappears and my console shows

 // [object Error]
 {}

Here is an example of what I'm trying to do that produces the same results.

const root = ReactDOM.createRoot(document.getElementById("wrapper"));

class Tester extends React.Component {
  constructor(props) {
    super(props);
    this.state = { num: 1, html: "<b>Odd</b>" };
  }
  handleClick() {
    let num = this.state.num + 1;
    let html = "<b>Odd</b>";
    if (num % 2 == 0) {
      html = "<i>Even</i>";
    }
    this.setState({ num: num, html: html });
  }
  render() {
    return (
      <div>
        <h1>Hello {this.state.num}</h1>{" "}
        <button onClick={this.handleClick.bind(this)}>Click</button>
        {/*<div>{this.state.html}</div>*/}
        <div dangerouslySetInnerHTML={{ __HTML: this.state.html }}></div>
      </div>
    );
  }
}

root.render(<Tester />);

I'll note that I am working in CodePen, but that doesn't seem to be the issue. I've found others using this method that work just fine. The link to that CodePen is https://codepen.io/chefdaddyjay/pen/RwyxgeE If you move the comments down a line in the code above, it works, but displays the HTML tags plainly.

Answer 1

the "html" inside the brackets should be lowercase like this

<div dangerouslySetInnerHTML={{ __html: this.state.html }}></div>

as per the documentation https://reactjs.org/docs/dom-elements.html#dangerouslysetinnerhtml (emphasis mine)

you have to type out dangerouslySetInnerHTML and pass an object with a __html key, to remind yourself that it's dangerous.