Hi struggle atm with a form which is implemented on the frontend. I want to save the formdata in an enquiry object which has a many_many relation to my groups object. And in return the groups object has as belongs_many_many relation to the enquiry object. So far so good. Now i create the form for the frontend and run into an issue with the Listboxfield. I cant get it to save the selected groups. How can i do that ??

so my controller looks like that

class EnquiryPage_Controller extends Page_Controller {
   function EnquiryForm() {

      $groups = DataObject::get("GroupHolder",""); // getting all pages for the groups
      $map = $groups->toDropDownMap();

      $fields = new FieldSet(
         new TextField('Title'),
         new TextField('Text'),
         new ListboxField('Groups','Groups',$map,$map[0],5,true)
      );

// Create actions
$actions = new FieldSet(
new FormAction('doForm', 'Submit')
);

$validator = new RequiredFields('Title', 'Text');

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

function doForm($data, $form) {
$submission = new EnquiryObject();
    $form->saveInto($submission);
$submission->write();

Director::redirectBack();
}

}

Would be awesome if someone could help me with my issue.

I also had some problems finding a way of adding many_many relations via the frontend!

But the solution ist actually quite easy, once you find the "Class ComponentSet" http://api.silverstripe.org/default/ComponentSet.html

Here my solution:

Hope this helps!