useeffect hooks react code example
Example 1: useeffect umnount
useEffect(() => {
return () => {
console.log("cleaned up");
};
}, []);
Example 2: useeffect with cleanup
useEffect(() => {
//your code goes here
return () => {
//your cleanup code codes here
};
},[]);
Example 3: useEffect
import React, { useState, useEffect } from 'react';
function Example() {
const [count, setCount] = useState(0);
// Similar to componentDidMount and componentDidUpdate:
useEffect(() => {
// Update the document title using the browser API
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
import React, { useEffect } from 'react';
const [data,setData]=useState()
useEffect(() => {
fetch(`put your url/api request in here`)
.then(res=>res.json())
.then(json => setData(json))
},[])
Example 5: 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>
);
}