maxLengthValidator function

String? maxLengthValidator(
  1. String? value,
  2. int maxLength, {
  3. String? message,
})

Field must be at most maxLength characters (blank passes).

Implementation

String? maxLengthValidator(String? value, int maxLength, {String? message}) {
  if (value == null || value.trim().isEmpty) return null;
  return value.length <= maxLength
      ? null
      : message ?? 'Must be at most $maxLength characters';
}