验证 laravel 验证中的两个字段

validation two fileds in laravel validation

我有 2 个字段要检查验证...

parent
tag

我想要这样的东西:

if(parent == 0)
     return 'tag is required';
else 
    return 'tag can be nullable';

我试过这样的方法,但它是错误的:

'parent' => 'nullable|numeric',
'tags' => 'required_with:parent=0|array|max:8',

使用required_if规则。

The field under validation must be present and not empty if the anotherfield field is equal to any value.

'parent' => 'nullable|numeric',
'tags' => 'required_if:parent,0|array|max:8',

https://laravel.com/docs/5.5/validation#rule-required-if