Flask-WTF for form validation - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to import the FlaskForm base class from Flask-WTF.

Flask

from flask_wtf import [1]

Drag options to blanks, or click blank then click option'

ABaseForm

BFlaskForm

CFormBase

DForm

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'Form' instead of 'FlaskForm' causes import errors.

Trying to import 'FormBase' which does not exist in Flask-WTF.

The FlaskForm class is the base class for creating forms in Flask-WTF.

2fill in blank

medium

Complete the code to define a text input field named 'username' using WTForms.

Flask

from wtforms import StringField

class LoginForm(FlaskForm):
    username = [1]('Username')

Drag options to blanks, or click blank then click option'

ATextField

BCharField

CInputField

DStringField

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'TextField' which is deprecated in WTForms.

Using 'CharField' which is not part of WTForms.

StringField is the correct WTForms field type for text input.

3fill in blank

hard

Fix the error in the code to add a required validator to the email field.

Flask

from wtforms.validators import DataRequired, Email

class ContactForm(FlaskForm):
    email = StringField('Email', validators=[[1]])

Drag options to blanks, or click blank then click option'

ADataRequired()

BRequired()

CEmail()

DInputRequired()

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'Required()' which is deprecated.

Using 'Email()' which only checks email format, not presence.

DataRequired() ensures the field is not empty. It is the correct validator for required input.

4fill in blank

hard

Fill both blanks to create a password field with a length validator requiring 6 to 12 characters.

Flask

from wtforms import PasswordField
from wtforms.validators import Length

class RegisterForm(FlaskForm):
    password = PasswordField('Password', validators=[Length(min=[1], max=[2])])

Drag options to blanks, or click blank then click option'

A6

B12

C8

D10

Attempts:

3 left

💡 Hint

Common Mistakes

Swapping min and max values.

Using values outside the required range.

The Length validator requires min=6 and max=12 to enforce password length between 6 and 12 characters.

5fill in blank

hard

Fill all three blanks to create a form with a submit button labeled 'Send', a CSRF token, and a text area field named 'message'.

Flask

from flask_wtf import FlaskForm
from wtforms import SubmitField, TextAreaField

class MessageForm(FlaskForm):
    message = [1]('Message')
    submit = [2]('Send')

# CSRF protection is enabled by default with [3]

Drag options to blanks, or click blank then click option'

ATextAreaField

BSubmitField

CFlaskForm

DStringField

Attempts:

3 left

💡 Hint

Common Mistakes

Using StringField instead of TextAreaField for message.

Forgetting that CSRF is enabled by FlaskForm.

TextAreaField creates a multi-line text input, SubmitField creates a submit button, and FlaskForm enables CSRF protection automatically.