react hook component did mount code example
Example 1: react hooks componentdidmount
useEffect(() => {
}, []);
Example 2: react useEffect
import React, { useEffect } from 'react';
export const App: React.FC = () => {
useEffect(() => {
}, [])
return (
<div>Use Effect!</div>
);
}
Example 3: componentwillunmount hooks
useEffect(() => {
window.addEventListener('mousemove', () => {});
return () => {
window.removeEventListener('mousemove', () => {})
}
}, [])
Example 4: componentdidmount functional hook
import { useState, useEffect } from 'react';
function getWindowDimensions() {
const { innerWidth: width, innerHeight: height } = window;
return {
width,
height
};
}
export default function useWindowDimensions() {
const [windowDimensions, setWindowDimensions] = useState(getWindowDimensions());
useEffect(() => {
function handleResize() {
setWindowDimensions(getWindowDimensions());
}
window.addEventListener('resize', handleResize);
return () => window.removeEventListener('resize', handleResize);
}, []);
return windowDimensions;
}