React & Modern Frontend (445 Qs)•Part 11: Legacy Architecture, Migration Patterns & Historical Internals (354 - 445)
What are the possible ways of updating objects in state?
-
Calling
setState()with an object to merge with state:css- Using `Object.assign()` to create a copy of the object:
javascript
const user = Object.assign({}, this.state.user, { age: 42 });
this.setState({ user });
markdown
- Using _spread operator_:
javascript
const user = { ...this.state.user, age: 42 };
this.setState({ user });
javascript
2. **Calling `setState()` with a function:**
javascript
this.setState((prevState) => ({
user: {
...prevState.user,
age: 42,
},
}));