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@kachar
Created September 7, 2022 08:06
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import { Dispatch, SetStateAction, useState } from 'react'
export default function useLocalStorage<T>(
key: string,
initialValue: T,
): [T, Dispatch<SetStateAction<T>>] {
// State to store our value
// Pass initial state function to useState so logic is only executed once
const [storedValue, setStoredValue] = useState<T>(() => {
if (typeof window === 'undefined') {
return initialValue
}
try {
// Get from local storage by key
const item = window.localStorage.getItem(key)
// Parse stored json or if none return initialValue
return item ? JSON.parse(item) : initialValue
} catch (error) {
// If error also return initialValue
console.log(error)
return initialValue
}
})
// Return a wrapped version of useState's setter function that ...
// ... persists the new value to localStorage.
const setValue: Dispatch<SetStateAction<T>> = (value) => {
try {
// Allow value to be a function so we have same API as useState
const valueToStore = value instanceof Function ? value(storedValue) : value
// Save state
setStoredValue(valueToStore)
// Save to local storage
if (typeof window !== 'undefined') {
window.localStorage.setItem(key, JSON.stringify(valueToStore))
}
// We dispatch a custom event so every useLocalStorage hook are notified
window.dispatchEvent(new Event('local-storage'))
} catch (error) {
// A more advanced implementation would handle the error case
console.log(error)
}
}
return [storedValue, setValue]
}
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