NotIn

Validates that a value is not included in the given array

  • return (boolean)

In your code

if(v::notIn('A', array('B', 'C', 'D'))) {
  echo 'Yay, valid!';
}

In fields

fields:
  example:
    label: Example field
    type: text
    validate:
      notIn:
        - B
        - C
        - D