UID

To generate a stable UID/Key for a given

item

Example - https://codesandbox.io/s/kkmwr6vv47

API

React UID provides 3 different APIs - vanilla js API -

uid(item) -> key

{ id => <>>}

useUID

Javascript

• uid(item, [index])

  - generates UID for an object(array, function and so on), result could be used as React

  key

  .

  item

  should be an object, but could be anything. In case it is not an "object", and might have non-unique value - you have to specify second argument -

  index

  ```js import {uid} from 'react-uid';

// objects const data = [{a:1}, {b:2}]; data.map( item =>

// unique strings const data = ["a", "b"]; data.map( item =>

// strings const data = ["a", "a"]; data.map( (item, index) =>

JS API might be NOT (multi-tenant)SSR friendly,

React Components

• (deprecated)

  UID

  - renderless container for generation Ids

• UIDConsumer

  - renderless container for generation Ids ```js import {UID} from 'react-uid';

{id => ( )}

// you can apply some "naming conventions" to the keys

unique-${id}

// UID also provide

uid

// in the case

item

The difference between

and

versions are in "nesting" - any

used inside another

would contain "parent prefix" in the result, scoping

UID might be NOT SSR friendly,

Hooks (16.8+)

• useUID()

  will generate a "stable" UID

• useUIDSeed()

  will generate a seed generator, you can use for multiple fields ```js import { useUID, useUIDSeed } from 'react-uid';

const Form = () => { const uid = useUID();
return ( <> Email: </> ) }

const Form = () => { const seed = useUIDSeed();
return ( <> Email: {data.map(item =>

Server-side friendly UID

• UIDReset

  ,

  UIDConsumer

  ,

  UIDFork

  - SSR friendly UID. Could maintain consistency across renders. They are much more complex than

  UID

  , and provide functionality you might not need.

The key difference - they are not using global "singlentone" to track used IDs, but read it from Context API, thus works without side effects.

Next example will generate the same code, regardless how many time you will render it ```js import {UIDReset, UIDConsumer} from 'react-uid';

{(id,uid) => ( data.map( item =>

UID is not 100% SSR friendly - use UIDConsumer.

Code splitting

Codesplitting may affect the order or existence of the components, so alter the

componentDidMount

In case of SPA, this is not something you should be bothered about, but for SSR this could be fatal.

Next example will generate consistent keys regardless of component mount order. Each call to

UIDFork

{ uid => {uid} is unique } { uid => {uid} is unique }
```

The hooks API only needs the

So hard?

"Basic API" is not using Context API to keep realization simple, and React tree more flat.

Types

Written in TypeScript

Licence

MIT