消息为您的字段如下。

$messages = array(
    'cat.required' => 'The category field is required.',
);

$validator = Validator::make($input, $rules, $messages);

请参阅 laravel文档中的自定义错误消息部分以获取更多信息。

Please see Custom Error Messages section in laravel documentation for more information.

或者您可以为您的字段名称保留一个映射，如下所示。你可以将这些设置为你的验证器。所以你可以看到描述性的名字，而不是真正的字段名。

Or you can keep a mapping for your field names like below. And you can set those into you validator. So you can see descriptive name instead of real field name.

$attributeNames = array(
   'name' => 'Name',
   'cat' => 'Category',     
);

$validator = Validator::make ( Input::all (), $rules );
$validator->setAttributeNames($attributeNames);