For example we have such state:
state = { hasSomething: true, anotherKey: '', ... }
and we should update only 'hasSomething':
static getDerivedStateFromProps(nextProps) {
if (nextProps.accessKey === 'admin') {
return {
hasSomething: false,
};
}
return null;
}
do we need to destruct the prevState when we return new state? for example like this:
static getDerivedStateFromProps(nextProps, prevState) {
if (nextProps.accessKey === 'admin') {
return {
...prevState,
hasSomething: false,
};
}
return null;
}
or we don't need it? i checked the console.log(this.state) and it returns the whole local state if im not make a prevState destructing.
i can't find this information in official react documentation :(
P.S. this logic just an example :)
The official documentation says It should return an object to update the state, or null to update nothing. (https://reactjs.org/docs/react-component.html#static-getderivedstatefromprops). It is not cleared the state when you return only part of it, so it works like setState (https://reactjs.org/docs/react-component.html#setstate). The setState documentation says
You may optionally pass an object as the first argument to setState() instead of a function. This performs a shallow merge of stateChange into the new state., so you don't need to destruct the previous state.