如何将空值添加到Silverstripe DropDownField并要求选择非空值？

Question

如何将空值添加到Silverstripe DropDownField并要求选择非空值？

目前，我的领域是：

$myField = new DropdownField(
  'MyField',
  "So what'll it be, yes or no?",
  array( "N"=>"No", "Y"=>"Yes")
);

使用SilverStripe 3.1

Answer 1

您想要设置

$myField->setHasEmptyDefault(true);

然后使用控制器中的Form validation。

类似的东西：

public function myForm() {
    $myField = new DropdownField(
        'MyField',
        "So what'll it be, yes or no?",
        array( "N"=>"No", "Y"=>"Yes")
    );
    $fields = new FieldList($myField);
    $validator = new RequiredFields('MyField');

    return new Form($this, 'myFormForm', $fields, $actions, $validator);
}