useeffect state change code example
Example 1: react use effect
useEffect(() => {
},[]);
Example 2: useeffect with cleanup
useEffect(() => {
return () => {
};
},[]);
Example 3: useEffect
import React, { useState, useEffect } from 'react';
function Example() {
const [count, setCount] = useState(0);
useEffect(() => {
document.title = `You clicked ${count} times`;
});
return (
<div>
<p>You clicked {count} times</p>
<button onClick={() => setCount(count + 1)}>
Click me
</button>
</div>
);
}
Example 4: react useeffect on change props
useEffect(() => console.log('value changed!'), [props.isOpen]);
Example 5: useeffect on update
const isInitialMount = useRef(true);
useEffect(() => {
if (isInitialMount.current) {
isInitialMount.current = false;
} else {
}
});