how to use prevstate to localstorage in typescript(react) - reactjs

Question

type allergyProps = {
filterAllergy: allergyArray[];
setRemoveAllergy: Dispatch<SetStateAction<string>>;
setSearchAllergy: Dispatch<SetStateAction<string>>;
};
type allergyArray = {
id: number;
name: string;
};
const Allergy = ({ setSearchAllergy, filterAllergy }: allergyProps) => {
const [isInput, setIsInput] = useState(false);
const [removeAllergy, setRemoveAllergy] = useState<string[]>([]);
const handleInput = (e: React.ChangeEvent<HTMLInputElement>) => {
if (e.target.value) {
setIsInput(true);
} else {
setIsInput(false);
}
setSearchAllergy(e.target.value);
};
const click = (e: React.MouseEvent<HTMLButtonElement>) => {
let value = e.currentTarget.name;
setRemoveAllergy([...removeAllergy, value]);
localStorage.setItem("allergy", removeAllergy); << #####error point !#######
};
error name is
Argument of type 'string[]' is not assignable to parameter of type 'string'.
29 | let value = e.currentTarget.name;
30 | setRemoveAllergy([...removeAllergy, value]);
> 31 | localStorage.setItem("allergy", removeAllergy);
| ^^^^^^^^^^^^^
32 | };
i want use to prevState for setItem,,
how to use prevState of array type?

Answer 1

localStorage cannot hold any data type except for strings. If you would still like to force it, you can convert the array into a string and then place it in localStorage as follows:
localStorage.setItem("allergy", JSON.stringify(removeAllergy));
When you want to read from localStorage, you would need to do this to get it back into the form of an array:
JSON.parse(localStorage.getItem("allergy"));