React 18: Handling Form Validation with Multiple Nested States and Custom scenarios Messages
Does anyone know how to I've searched everywhere and can't find a clear answer. I've looked through the documentation and I'm still confused about I'm currently working on a form in React 18 that has multiple nested state objects for managing user input, and I need to implement custom validation with specific behavior messages based on user interactions. The form consists of a user profile section with fields for first name, last name, and age, and I want to display behavior messages dynamically based on the user's input. I have the following form structure: ```jsx const [formData, setFormData] = useState({ profile: { firstName: '', lastName: '', age: '' }, errors: {} }); ``` I'm trying to validate the input fields on change and store behavior messages in the `errors` object. Here’s how I’ve set up my `handleChange` function: ```jsx const handleChange = (e) => { const { name, value } = e.target; setFormData((prevData) => { const newErrors = { ...prevData.errors }; // Example validation if (name === 'firstName' && value.trim() === '') { newErrors.firstName = 'First Name is required'; } else { delete newErrors.firstName; } return { ...prevData, profile: { ...prevData.profile, [name]: value }, errors: newErrors }; }); }; ``` The question I’m working with is that the behavior messages are not updating as expected when I type in the input fields. They only show the errors after I leave the input field (on blur), rather than updating dynamically with each keystroke. I would like the behavior messages to reflect the current state of the input field in real-time. I've tried using the `useEffect` hook to trigger validation every time the input changes, but I ended up re-validating on every render, which caused performance optimization and unnecessary re-renders. Here’s an excerpt of what I attempted: ```jsx useEffect(() => { const newErrors = {}; if (formData.profile.firstName.trim() === '') { newErrors.firstName = 'First Name is required'; } setFormData((prev) => ({ ...prev, errors: newErrors })); }, [formData.profile.firstName]); ``` However, this approach doesn’t seem optimal. What’s the best way to handle real-time validation for nested state objects in React? Is there a better pattern I should be following to ensure performance and responsiveness while validating form input? How would you solve this? The stack includes Javascript and several other technologies. Has anyone dealt with something similar? What's the correct way to implement this?