Function maxValidator

packages/forms/src/validators.ts:486–496

(max: number)

 * See `Validators.max` for additional information.
 */
export function maxValidator(max: number): ValidatorFn {
  return (control: AbstractControl): ValidationErrors | null => {
    if (control.value == null || max == null) {
      return null; // don't validate empty values to allow optional controls
    }
    const value = parseFloat(control.value);
    // Controls with NaN values after parsing should be treated as not having a
    // maximum, per the HTML forms spec: https://www.w3.org/TR/html5/forms.html#attr-input-max
    return !isNaN(value) && value > max ? {'max': {'max': max, 'actual': control.value}} : null;
  };
}

/**
 * Validator that requires the control have a non-empty value.