Validate a single variable or an array in Laravel - laravel

Question

I want to validate a single variable like this $name = "example name" but I didn't a way to handle it then I decided to convert it to an array like this $nameArr = ['name' => 'example name'];, the validator is
$rules =
$this->validate($nameArr, [
'name' => 'required|max:10|regex:/^[a-zA-Z0-9]+$/u',
], [
'name.required' => 'name is empty',
'name.max' => 'name must be more less than 10 letters',
'name.regex' => 'invalid name'
]
);
but the Laravel gives this error
Argument 1 passed to App\Http\Controllers\Controller::validate() must be an instance of Illuminate\Http\Request, string given

Answer 1

Correct, the validate function on Controller comes from Illuminate\Foundation\Validation\ValidatesRequests and requires the first paramter to be a request object.
If you want to validate an array, you will have to create the validator manually.
$validator = Validator::make($nameArr,
[
'name' => 'required|max:10|regex:/^[a-zA-Z0-9]+$/u',
],
[
'name.required' => 'name is empty',
'name.max' => 'name must be more less than 10 letters',
'name.regex' => 'invalid name'
]
);
if ($validator->fails()) {
dd($validator->errors());
}

Answer 2

After knowing that the parameter is passed as route url param, I would like to add another option which Laravel provides to validate :
Route::get('user/{name}', 'UserProfileController#getByName')
->where([ 'name' => '[a-z]{10,}' ]);
The where method validates the route param based on provided regular expressions. So [a-z]{10,} will make sure the name is present with 10 or more characters.
See documentation for more