validateAge static method

String? validateAge(
  1. int? age, {
  2. int min = 18,
  3. int max = 120,
})

Validate age

Implementation

static String? validateAge(int? age, {int min = 18, int max = 120}) {
  if (age == null) {
    return 'Age is required.';
  }

  if (age < min) {
    return 'You must be at least $min years old.';
  }

  if (age > max) {
    return 'Please enter a valid age.';
  }

  return null;
}