Laravel provides robust tools for validating form data. 1. Basic validation can be done using the validate() method in controllers, ensuring fields meet criteria like required, max length, or unique values. 2. For complex scenarios, form requests encapsulate validation logic into dedicated classes, improving code organization. 3. Custom error messages can be defined to enhance user feedback, and errors are easily displayed in Blade views using directives. 4. Best practices include using @csrf, handling unique rule exceptions during updates, applying conditional validation with sometimes(), and testing edge cases to ensure reliability.

Validating form data in Laravel is straightforward thanks to its built-in validation system. Whether you're building a simple contact form or handling complex user input, Laravel provides clean and powerful tools to make sure the data meets your requirements.

Basic Form Validation with Request Data

The most common way to validate form data is by using the validate() method on the incoming request object inside your controller method.

For example, if you have a form that submits a user's name and email, you can validate it like this:

public function store(Request $request)
{
    $validatedData = $request->validate([
        'name' => 'required|max:255',
        'email' => 'required|email|unique:users',
    ]);

    // If validation passes, proceed with storing the data
}

In this case:

• The name field must be present and no longer than 255 characters.
• The email must be present, formatted correctly as an email address, and not already taken in the users table.

If validation fails, Laravel automatically returns a response redirecting the user back with errors, which you can display in your form view.

Using Form Requests for Complex Validation

As your validation logic becomes more complex—like needing custom rules, authorization checks, or reusable validation across multiple controllers—you should use form requests.

A form request is a custom request class that handles all the validation logic for a specific form. You can generate one using Artisan:

php artisan make:request StoreUserRequest

Then, define your rules in the generated file (app/Http/Requests/StoreUserRequest.php):

public function rules()
{
    return [
        'name' => 'required|max:255',
        'email' => 'required|email|unique:users',
        'password' => 'required|min:6',
    ];
}

Now, type-hint the request in your controller method:

public function store(StoreUserRequest $request)
{
    $validatedData = $request->validated();

    // Save user or perform actions
}

This keeps your controller clean and separates concerns nicely.

Custom Error Messages and Displaying Errors in Views

Laravel allows you to customize error messages easily. In either approach (inline validation or form requests), you can provide custom messages like this:

$request->validate([
    'title' => 'required|max:100',
], [
    'title.required' => 'A title is required',
    'title.max' => 'Title cannot exceed 100 characters',
]);

When displaying errors in Blade templates, Laravel makes it easy too. For example:

@if ($errors->has('email'))
    <span class="error">{{ $errors->first('email') }}</span>
@endif

Or loop through all errors:

@foreach ($errors->all() as $error)
    <div>{{ $error }}</div>
@endforeach

A Few Tips to Keep in Mind

Here are some small but important things that can save you time:

• Make sure your form uses the @csrf directive—otherwise, Laravel will block the request.
• When updating existing records (like in an edit form), use unique:users,email,{{ $user->id }} to exclude the current user from the unique check.
• Use sometimes() when certain fields need conditional validation based on other inputs.
• Always test edge cases—like empty strings, very long values, or invalid formats—to ensure your validation behaves as expected.

Basically, Laravel gives you solid tools right out of the box. It’s just a matter of choosing the right approach based on your form’s complexity.

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