Validation in Laravel

avoid space in username.

'username' => ['required', 'string', 'max:255', 'unique:users', 'regex:/^\S*$/u'],

alpha_dash is a default Laravel validation rule which allows letters, numbers, dashes and underscores and NOT space.

'username' => ['required', 'string', 'max:255', 'unique:users', 'alpha_dash'],

Laravel 5.7,5.8:

return Validator::make($data, [
             'A' => ['required', 'string'],
             'B' => ['required', 'string', 'max:255'],
            ]);

Older versions:

return Validator::make($data, [
             'A' => 'required|string',
             'B' => 'required|string|max:255',
            ]);



$rule=array(
                'first_name' => 'required',
                'last_name' => 'required',
                'email' => 'required|email|max:75|unique:users',
                'mobile' => 'required|regex:/^([0-9\s\-\+\(\)]*)$/|min:10',
                'password' => 'required|min:3|confirmed'
                 );

40 Additional Laravel Validation Rules

https://laraveldaily.com/40-additional-laravel-validation-rules/

https://laraveldaily.com/how-to-create-custom-validation-rules-laravel/