how to countdown timer in react code example
Example 1: countdown in react js
import React from 'react'
import { useState, useEffect } from 'react';
const Timer = (props:any) => {
const {initialMinute = 0,initialSeconds = 0} = props;
const [ minutes, setMinutes ] = useState(initialMinute);
const [seconds, setSeconds ] = useState(initialSeconds);
useEffect(()=>{
let myInterval = setInterval(() => {
if (seconds > 0) {
setSeconds(seconds - 1);
}
if (seconds === 0) {
if (minutes === 0) {
clearInterval(myInterval)
} else {
setMinutes(minutes - 1);
setSeconds(59);
}
}
}, 1000)
return ()=> {
clearInterval(myInterval);
};
});
return (
<div>
{ minutes === 0 && seconds === 0
? null
: <h1> {minutes}:{seconds < 10 ? `0${seconds}` : seconds}</h1>
}
</div>
)
}
export default Timer;
Example 2: countdown timer in seconds react
function App() {
const [seconds, setSeconds] = React.useState(10);
React.useEffect(() => {
if (seconds > 0) {
setTimeout(() => setSeconds(seconds - 1), 1000);
} else {
setSeconds('BOOOOM!');
}
});
return (
<div className="App">
<div>
{seconds}
</div>
</div>
);
}