Custom Validators and Field Errors
Write rules and surface messages to users.
Beyond Built-Ins
Built-in validators cover the basics, but real apps have unique rules. Now you will write custom validators and surface clear errors. ✍️
Recall the Standard Set
You already know DataRequired, Length, and Email. Custom rules layer on top of these for logic the library cannot guess.
from wtforms.validators import DataRequired, Length, EmailAll lessons in this course
- Define a FlaskForm Class
- Render and Submit a Form
- validate_on_submit and CSRF Tokens
- Custom Validators and Field Errors