react-timer-hook

React timer hook is a custom react hook, built to handle timer, stopwatch, and time logic/state in your react component.

1. useTimer: Timers (countdown timer)
2. useStopwatch: Stopwatch (count up timer)
3. useTime: Time (return current time)

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Setup

yarn add react-timer-hook OR npm install --save react-timer-hook

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useTimer - Demo

$3

``javascript
import React from 'react';
import { useTimer } from 'react-timer-hook';

function MyTimer({ expiryTimestamp }) {
const {
totalSeconds,
milliseconds,
seconds,
minutes,
hours,
days,
isRunning,
start,
pause,
resume,
restart,
} = useTimer({ expiryTimestamp, onExpire: () => console.warn('onExpire called'), interval: 20 });


return (


| key | Type | Required | Description |
| --- | --- | --- | ---- |
| expiryTimestamp | Date object | YES | this will define for how long the timer will be running |
| autoStart | boolean | No | flag to decide if timer should start automatically, by default it is set to true |
| interval | number | No | value to change the interval of the timer, by default it is set to 1000ms. Note: this value will not affect the timer, it will just define the frequency used to calculate the current timer values. For example, if you have a use case where milliseconds are used, you need to use a smaller value for the interval, for example, 20ms or 100ms based on your needs. |
| onExpire | Function | No | callback function to be executed once countdown timer is expired |

$3

| key | Type | Description |
| --- | --- | ---- |
| milliseconds | number | milliseconds value, to get accurate ms values you need to set interval to a smaller value example: 20ms |
| seconds | number | seconds value |
| minutes | number | minutes value |
| hours | number | hours value |
| days | number | days value |
| totalSeconds | number | total number of seconds left in timer NOT converted to minutes, hours or days |
| totalMilliseconds | number | total number of milliseconds left in timer NOT converted to minutes, hours or days |
| isRunning | boolean | flag to indicate if timer is running or not |
| pause | function | function to be called to pause timer |
| start | function | function if called after pause the timer will continue based on original expiryTimestamp |
| resume | function | function if called after pause the timer will continue countdown from last paused state |
| restart | function | function to restart timer with new expiryTimestamp, accept 2 arguments first is the new expiryTimestamp of type Date object and second is autoStart of type boolean to decide if it should automatically start after restart or not, default is true |


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useStopwatch - Demo

$3

`javascript
import React from 'react';
import { useStopwatch } from 'react-timer-hook';

function MyStopwatch() {
const {
totalSeconds,
milliseconds,
seconds,
minutes,
hours,
days,
isRunning,
start,
pause,
reset,
} = useStopwatch({ autoStart: true, interval: 20 });


return (


| key | Type | Required | Description |
| --- | --- | --- | ---- |
| autoStart | boolean | No | if set to true stopwatch will auto start, by default it is set to false |
| offsetTimestamp | Date object | No | this will define the initial stopwatch offset example: const stopwatchOffset = new Date(); stopwatchOffset.setSeconds(stopwatchOffset.getSeconds() + 300); this will result in a 5 minutes offset and stopwatch will start from 0:0:5:0 instead of 0:0:0:0 |
| interval | number | No | value to change the interval of the stopwatch, by default it is set to 1000ms. Note: this value will not affect the stopwatch, it will just define the frequency used to calculate the current timer values. For example, if you have a use case where milliseconds are used, you need to use a smaller value for the interval, for example, 20ms or 100ms based on your needs. |

$3

| key | Type | Description |
| --- | --- | ---- |
| milliseconds | number | milliseconds value, to get accurate ms values you need to set interval to a smaller value example: 20ms |
| seconds | number | seconds value |
| minutes | number | minutes value |
| hours | number | hours value |
| days | number | days value |
| totalSeconds | number | total number of seconds in stopwatch NOT converted to minutes, hours or days |
| isRunning | boolean | flag to indicate if stopwatch is running or not |
| start | function | function to be called to start/resume stopwatch |
| pause | function | function to be called to pause stopwatch |
| reset | function | function to be called to reset stopwatch to 0:0:0:0, you can also pass offset parameter to this function to reset stopwatch with offset, similar to how offsetTimestamp will offset the initial stopwatch time, this function will accept also a second argument which will decide if stopwatch should automatically start after reset or not default is true |


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useTime - Demo

$3

`javascript
import React from 'react';
import { useTime } from 'react-timer-hook';

function MyTime() {
const {
milliseconds,
seconds,
minutes,
hours,
ampm,
} = useTime({ format: '12-hour', interval: 20 });

return (


| key | Type | Required | Description |
| --- | --- | --- | ---- |
| format | string | No | if set to 12-hour time will be formatted with am/pm |
| interval | number | No | value to change the interval of the time, by default it is set to 1000ms. Note: this value will not affect the thime, it will just define the frequency used to calculate the current time values. For example, if you have a use case where milliseconds are used, you need to use a smaller value for the interval, for example, 20ms or 100ms based on your needs. |

$3

| key | Type | Description |
| --- | --- | ---- |
| milliseconds | number | milliseconds value |
| seconds | number | seconds value |
| minutes | number | minutes value |
| hours | number | hours value |
| ampm | string | am/pm value if 12-hour format is used |


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$3

Starting from v1.1.0 and above default export useTimer is deprecated, your old code will still work but it is better to start using named exports { useTimer, useStopwatch, useTime }`