The file input Tag
//shows how to create a ref to the DOM node to access file(s) in a submit handler
class FileInput extends React.Component {
constructor(props) {
super(props);
this.handleSubmit = this.handleSubmit.bind(this);
this.fileInput = React.createRef();
}
handleSubmit(event) {
event.preventDefault();
alert(
`Selected file - ${
this.fileInput.current.files[0].name
}`
);
}
render() {
return (
<form onSubmit={this.handleSubmit}>
<label>
Upload file:
<input type="file" ref={this.fileInput} />
</label>
<br />
<button type="submit">Submit</button>
</form>
);
}
}
ReactDOM.render(
<FileInput />,
document.getElementById('root')
);
It is an uncontrolled component in React because its value is read-only.
Lets the user choose one or more files from their device storage to be uploaded to a server or manipulated by JavaScript via the File API.