useEffect()

 THE EFFECT HOOK LET'S YOU PERFORM SIDE EFFECTS IN FUNCTION COMPONENT.

 IF WE WANT TO PERFORM A TASK WHENEVER A COMPONENT RENDERS, WE USE useEffect().

WHENVER A CHANGE IS TRACKED AND WE WANT TO PERFORM A TASK BY THAT CHANGE, THESE TASKS ARE CALLED AS SIDE EFFECTS, IN REACT THEY ARE KNOWN AS EFFECTS.

DATA FETCHING, SETTING UP A SUBSCRIPTION AND MANUALLY CHANGING THE DOM IN REACT COMPONENTS ARE ALL EXAMPLES OF SIDE EFFECTS.

WHENEVER THERE IS A CHANGE IN STATE, THESE SIDE EFFECTS WORK.

import { useEffect, useState } from "react";

export default function Counter() {
  let [count, setCount] = useState(0);
  let inc = () => {
    setCount((currCount) => currCount + 1);
  };
  useEffect(function PrintSomething() {
    console.log("this is a side effect");
  });
  return (
    <>
      <h2>Count:{count}</h2>
      <button onClick={inc}>+1</button>
    </>
  );
}





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