hooks lifecycle code example
Example 1: angular lifecycle hooks
AngularJS lifecycle hooks
Angular gives us 8 hooks to allow us to tap into the lifecycle of our components and trigger actions at specific points in the lifecycle.
1. ngOnChanges
2. ngOnInit
3. ngDoCheck
4. ngAfterContentInit
5. ngAfterContentChecked
6. ngAfterViewInit
7. ngAfterViewChecked
8. ngOnDestroy
Example 2: react useEffect
import React, { useEffect, useState } from 'react';
import ReactDOM from 'react-dom';
function LifecycleDemo() {
useEffect(() => {
console.log('render!');
return () => console.log('unmounting...');
}, [
return "I'm a lifecycle demo";
}
function App() {
const [random, setRandom] = useState(Math.random());
const [mounted, setMounted] = useState(true);
const reRender = () => setRandom(Math.random());
const toggle = () => setMounted(!mounted);
return (
<>
<button onClick={reRender}>Re-render</button>
<button onClick={toggle}>Show/Hide LifecycleDemo</button>
{mounted && <LifecycleDemo/>}
</>
);
}
ReactDOM.render(<App/>, document.querySelector('#root'));
Example 3: useeffect componentdidmount
import React, { useState, useEffect } from 'react';
function Example() {
const [count, setCount] = useState(0);
useEffect(() => {
document.title = `You clicked ${count} times`;
});
);
}
Example 4: react lifecycle hooks
class Content extends React.Component {
componentWillMount() {
this.setState({ activities: data });
}
}
Example 5: components react to hooks
import React, { useState } from 'react';
function Example() {
return (
<div>
<p>You clicked {count} times</p>
<button onClick={() => setCount(count + 1)}>
Click me
</button>
</div>
);
}
Example 6: react lifecycle hooks
class ActivityItem extends React.Component {
render() {
const { activity } = this.props;
return (
<div className='item'>
<div className={'avatar'}>
<img
alt='avatar'
src={activity.actor.avatar_url} />
</div>
<span className={'time'}>
{moment(activity.created_at).fromNow()}
</span>
<p>{activity.actor.display_login} {activity.payload.action}</p>
<div className={'right'}>
{activity.repo.name}
</div>
</div>
)
}
}