Basic Validation Patterns & Submit Handling
Apply simple form checks (required fields, length, basic email) and handle submit by preventing reload and reporting errors.
Why validate?
Goal: Add simple checks to forms and handle submit smoothly.
- Required fields
- Length checks
- Basic email pattern
Submit flow
A typical flow:
- onSubmit calls event.preventDefault()
- Run validations
- If no errors: proceed (send or show success)
- If errors: set state and display messages
All lessons in this course
- Controlled Forms with Multiple Inputs
- Basic Validation Patterns & Submit Handling
- Error Messages & Touched/Dirty States (Vanilla)