function TextInputWithFocusButton() {
const inputEl = useRef(null);
const onButtonClick = () => {
// `current` points to the mounted text input element
inputEl.current.focus();
};
return (
<>
<input ref={inputEl} type="text" />
<button onClick={onButtonClick}>Focus the input</button>
</>
);
}class MyComponent extends React.Component {
constructor(props) {
super(props);
this.myRef = React.createRef();
}
render() {
return <div ref={this.myRef} />;
}
}const refContainer = useRef(initialValue);
//useRef returns a mutable ref object whose .current property is initialized to the passed argument (initialValue).
//The returned object will persist for the full lifetime of the component.import { useRef } from "react";
function ExampleUseRef() {
const inputNode = useRef(null);
const onClick = () => {
inputNode.current.focus();
};
return (
<>
<input ref={inputNode} type="text" />
<button onClick={onClick}>Focus..</button>
</>
);
}class CustomTextInput extends React.Component {
constructor(props) {
super(props);
// create a ref to store the textInput DOM element
this.textInput = React.createRef();
this.focusTextInput = this.focusTextInput.bind(this);
}
focusTextInput() {
// Explicitly focus the text input using the raw DOM API
// Note: we're accessing "current" to get the DOM node
this.textInput.current.focus();
}
render() {
// tell React that we want to associate the <input> ref
// with the `textInput` that we created in the constructor
return (
<div>
<input
type="text"
ref={this.textInput} />
<input
type="button"
value="Focus the text input"
onClick={this.focusTextInput}
/>
</div>
);
}
}