React useRef Hook

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Wed Sep 21 2022 03:39:12 GMT+0000 (Coordinated Universal Time)

Saved by @joseleal #jsx

import { useState, useEffect, useRef } from "react";
import ReactDOM from "react-dom/client";

function App() {
  const [inputValue, setInputValue] = useState("");
  const previousInputValue = useRef("");

  useEffect(() => {
    previousInputValue.current = inputValue;
  }, [inputValue]);

  return (
    <>
      <input
        type="text"
        value={inputValue}
        onChange={(e) => setInputValue(e.target.value)}
      />
      <h2>Current Value: {inputValue}</h2>
      <h2>Previous Value: {previousInputValue.current}</h2>
    </>
  );
}

const root = ReactDOM.createRoot(document.getElementById('root'));
root.render(<App />);

https://www.w3schools.com/react/react_useref.asp

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