Request validation basics in Laravel - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is the purpose of request validation in Laravel?

Request validation ensures that the data sent by users meets the rules your application expects before processing it. It helps keep your app safe and reliable.

beginner

How do you validate a request in a Laravel controller using the validate method?

You call $request->validate([ 'field' => 'rules' ]) inside your controller method. Laravel checks the data and automatically redirects back with errors if validation fails.

beginner

What happens if validation fails when using $request->validate()?

Laravel automatically redirects the user back to the previous page with error messages and old input data, so the user can fix mistakes easily.

beginner

Name two common validation rules in Laravel and what they check.

required: Ensures the field is present and not empty.<br>email: Checks if the field contains a valid email address.

intermediate

How can you customize the error messages shown after validation fails?

You can pass a second argument to <code>validate()</code> with an array of custom messages, or define messages in a Form Request class for cleaner code.

Which Laravel method is commonly used to validate incoming request data inside a controller?

A $request->validate()

B validateRequest()

C checkValidation()

D validateInput()

The correct method is $request->validate(), which applies validation rules to the incoming data.

What does the 'required' validation rule check for?

A Field must be a number

B Field must be unique

C Field must be a valid email

D Field must be present and not empty

The 'required' rule ensures the field is present in the request and is not empty.

If validation fails, what does Laravel do by default?

A Redirects back with error messages

B Sends a success response

C Continues processing without errors

D Deletes the request data

Laravel redirects the user back to the previous page with error messages and old input.

Where can you define validation rules besides directly in the controller?

A In the database migration

B In the routes file

C In a Form Request class

D In the .env file

Form Request classes are dedicated classes to organize validation logic cleanly.

How do you provide custom error messages for validation rules?

A By editing the Laravel core files

B By passing a second argument to $request->validate() with messages

C By changing the database schema

D By modifying the routes file

You can pass an array of custom messages as the second argument to $request->validate().

Explain how Laravel handles request validation inside a controller using the validate method.

Think about what happens when data does not meet the rules.

Describe two common validation rules in Laravel and what they check for.

Focus on simple, frequently used rules.