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React Academy · Lesson

Validation Rules & Error Messages

Apply built-in validation rules (required, minLength, pattern) and display error messages.

Welcome

In this lesson you will add built-in validation rules to React Hook Form fields and display user-friendly error messages below each input.

Built-in Validation Rules

Pass a rules object as the second argument to register(). Built-in rules include: `required`, `minLength`, `maxLength`, `min`, `max`, `pattern`, and `validate`.
<input
  {...register('email', {
    required: 'Email is required',
    pattern: {
      value: /^[^@]+@[^@]+\.[^@]+$/,
      message: 'Invalid email address',
    },
  })}
/>

All lessons in this course

  1. Getting Started with React Hook Form
  2. Validation Rules & Error Messages
  3. Schema Validation with Zod
  4. Dynamic Fields with useFieldArray
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