# Forms & Validation (Flutter)

> Form, TextFormField, GlobalKey<FormState>, validators, focus management, input types

- 20 interview questions
- Mid-Level
- [Interview Questions: Flutter](https://sharpskill.dev/en/technologies/flutter/interview-questions.md)

## 1. What is the main role of the Form widget in Flutter?

**Answer**

The Form widget serves as a container to group and manage multiple form fields (FormField). It allows validating, saving, and resetting all fields in a single operation via FormState. Without Form, each field would need to be managed individually.

## 2. How to access FormState to trigger form validation?

**Answer**

To access FormState, a GlobalKey<FormState> must be assigned to the Form's key property. Then, the currentState property of this key provides access to FormState and its methods validate(), save(), and reset().

## 3. What is the difference between TextField and TextFormField?

**Answer**

TextFormField is a version of TextField integrated with Form. It inherits from FormField and has a validator property that automatically integrates with FormState.validate(). TextField cannot directly participate in grouped Form validation.

## 17 more questions available

- What does the validator property of a TextFormField return to indicate an error?
- What is the purpose of the autovalidateMode property of a Form?

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