useEffect uses code example
Example 1: useeffect
function App() {
const [count, setCount] = useState(0);
useEffect(() => {
longResolve().then(() => {
alert(count);
});
}, []);
return (
<div>
<button
onClick={() => {
setCount(count + 1);
}}
>
Count: {count}
</button>
</div>
);
}
Example 2: 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 3: how to use 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: 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 5: react hook useeffect
//This is a basic example, carefully read the docs as
//useEffect it's like componentDidMount/WillUnmount
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>
);
}