style(datefield, datetimefield: use constant

Author: btry

inc/field/datefield.class.php

@@ -42,6 +42,7 @@
 class DateField extends DatetimeField
 {
    const DATE_FORMAT = 'Y-m-d';
+   const DATE_ZERO   = '0000-00-00';
 
    public function getRenderedHtml($domain, $canEdit = true): string {
       if (!$canEdit) {
@@ -77,7 +78,7 @@ public static function getName(): string {
     */
    protected function getDateFromValue(string $value) {
       if (empty($value)) {
-         $value = '0000-00-00';
+         $value = self::DATE_ZERO;
       }
       $datetime = DateTime::createFromFormat(self::DATE_FORMAT, $value);
       if ($datetime !== false) {

inc/field/datetimefield.class.php

@@ -46,6 +46,7 @@ class DatetimeField extends PluginFormcreatorAbstractField
    protected $fields = null;
 
    const DATE_FORMAT = 'Y-m-d H:i:s';
+   const DATE_ZERO   = '0000-00-00 00:00:00';
 
    public function isPrerequisites(): bool {
       return true;
@@ -151,7 +152,7 @@ public static function canRequire(): bool {
     */
    protected function getDateFromValue(string $value) {
       if (empty($value)) {
-         $value = '0000-00-00 00:00:00';
+         $value = self::DATE_ZERO;
       }
       return DateTime::createFromFormat(self::DATE_FORMAT, $value);
    }