Forms Validation Guide

This guide will help you understand how to validate forms in our application. Validation is crucial for ensuring the integrity and security of the data submitted by users.

Common Validation Rules

Here are some common validation rules that you can apply to your forms:

Required: Ensures that a field is not empty.
Email: Validates that the input is a valid email address.
Number: Ensures that the input is a number.
Length: Validates the length of the input string.
Regex: Allows you to define a regular expression pattern for validation.

Example

Let's say you have a form with a "Username" field. You want to ensure that the username is required and must be between 3 and 20 characters long.

<form>
  <label for="username">Username:</label>
  <input type="text" id="username" name="username" required pattern=".{3,20}" title="Username must be between 3 and 20 characters long.">
  <input type="submit" value="Submit">
</form>

Resources

For more information on form validation, you can check out our Form Validation Best Practices.