laravel request custom validation code example

Example 1: how to add an custom error to validater error in laravel

if (request('event') == null) {
    $validator->errors()->add('event', 'Please select an event');
}

Example 2: custom rule laravel validation

public function store()
{
    $this->validate(request(), [
        'song' => [function ($attribute, $value, $fail) {
            if ($value <= 10) {
                $fail(':attribute needs more cowbell!');
            }
        }]
    ]);
}

Example 3: valdidate laravel if falid

$validator = Validator::make($request->all(), [
    'name' => 'required|min:2|max:255'
]);

if ($validator->fails()) {
    return view('view_name');
} else {
    return view('view_name');
}

Example 4: validate field for existing client laravel

unique:users,username,id,1 // table, field, idcolumn, value to ignore