javascript - React JS how to get script inside dangerouslySetInnerHTML executed

Question

How to get script inside dangerouslySetInnerHTML get executed?

class Page extends Component {

  render() {
    return (
      <script
        dangerouslySetInnerHTML={{ __html: `
          console.log('hello world');
          window.dataLayer = window.dataLayer || [];
          window.dataLayer.push({
            event: 'viewCart'
          });
        ` }}
      />
    );
  }
}

I can't get console.log('hello world') executed. Anybody can help? Thank you

Answer 1

Script elements don't get executed because of the way that react-dom creates them.

When ReactDOM.createElement receives a type of 'script' it uses .innerHTML instead of using document.createElement like you might expect.

var div = document.createElement('div');
div.innerHTML = '<script></script>';

var element = div.removeChild(div.firstChild);

Creating the script in this way sets the "parser-inserted" flag on that element to true. This flag tells the browser that it should not execute.

---

https://github.com/facebook/react/blob/c2a2d8a539bf02e40c43d36adc2826e228f30955/packages/react-dom/src/client/ReactDOMComponent.js#L406

https://developer.mozilla.org/en-US/docs/Web/API/Element/innerHTML#Security_considerations

https://www.w3.org/TR/2008/WD-html5-20080610/dom.html#innerhtml0