Given the following component, when I press down on the age selector and change the value to 15, such that I render a form without the driver license field, I get the error:
Uncaught Error: Rendered fewer hooks than expected. This may be caused by an accidental early return statement.
at invariant (react-dom.development.js:55)
at finishHooks (react-dom.development.js:11581)
at updateFunctionComponent (react-dom.development.js:14262)
at beginWork (react-dom.development.js:15103)
at performUnitOfWork (react-dom.development.js:17817)
at workLoop (react-dom.development.js:17857)
at HTMLUnknownElement.callCallback (react-dom.development.js:149)
at Object.invokeGuardedCallbackDev (react-dom.development.js:199)
at invokeGuardedCallback (react-dom.development.js:256)
at replayUnitOfWork (react-dom.development.js:17113)
at renderRoot (react-dom.development.js:17957)
at performWorkOnRoot (react-dom.development.js:18808)
at performWork (react-dom.development.js:18716)
at flushInteractiveUpdates$1 (react-dom.development.js:18987)
at batchedUpdates (react-dom.development.js:2210)
at dispatchEvent (react-dom.development.js:4946)
at interactiveUpdates$1 (react-dom.development.js:18974)
at interactiveUpdates (react-dom.development.js:2217)
at dispatchInteractiveEvent (react-dom.development.js:4923)
Example code below:
const {useState} = React;
function App() {
const [name, setName] = useState('Mary');
const [age, setAge] = useState(16);
if (age < 16) {
return (
<div>
Name:{' '}
<input
value={name}
onChange={e => {
setName(e.target.value);
}}
/>
<br />
Age:{' '}
<input
value={age}
type=number
onChange={e => {
setAge(+e.target.value);
}}
/>
</div>
);
}
const [license, setLicense] = useState('A123456');
return (
<div>
Name:{' '}
<input
value={name}
onChange={e => {
setName(e.target.value);
}}
/>
<br />
Age:{' '}
<input
value={age}
type=number
onChange={e => {
setAge(+e.target.value);
}}
/>
<br />
Driver License:{' '}
<input
value={license}
onChange={e => {
setLicense(e.target.value);
}}
/>
</div>
);
}
ReactDOM.render(<App />, document.querySelector('#app'));
<script src=https://unpkg.com/[email protected]/umd/react.development.js></script>
<script src=https://unpkg.com/[email protected]/umd/react-dom.development.js></script>
<div id=app></div>