SS_HTTPRequest could not be converted to a string - php

Question

I have a SilverStripe (3.4) Page with a form that would work if I didn't have a DataObject in it.
public function AntwortForm($ID) {
$Nummer = Vortest_Fragen::get()->byID($ID);
if ($Nummer) {
$Art=$Nummer->Art;
}
if ($Art == 'Normal') {
$fields = new FieldList(
TextAreaField::create('Antwort'),
HiddenField::create('ID', 'ID', $ID),
HiddenField::create('VortestID', 'VortestID', $this->request->param('ID')),
HiddenField::create('Aktion', 'Aktion', $this->request->param('Action'))
);
} else {
$Optionen = explode(';', $Nummer->Optionen);
$a = 'A';
for ( $i = 0 ; $i < count ($Optionen); $i++) {
$Op[$a] ='<div style="width:25px;display:inline;">' . $a . ')</div> ' . $Optionen[$i];
$a++;
}
$fields = new FieldList(
CheckboxSetField::create('Antwort', 'Antwort', $Op),
HiddenField::create('ID', 'ID', $ID),
HiddenField::create('VortestID', 'VortestID', $this->request->param('ID')),
HiddenField::create('Aktion', 'Aktion',$this->request->param('Action')),
HiddenField::create('Art', 'Art', $Nummer->Art)
);
}
$actions = new FieldList(
FormAction::create('AntwortEintragen', 'Eintragen')
);
$form = new Form($this, 'AntwortForm', $fields, $actions);
return $form;
}
function AntwortEintragen($data, $form) {
$Antwort = Vortest_Antwort::get()->filter(array('FrageID' => $data['ID'], 'SchreiberID' => Member::currentUserID()));
foreach($Antwort as $item) {
$item->delete();
}
foreach ($data['Antwort'] as $Antwort) {
$Ant .= $Antwort . ',';
}
$Antwort = new Vortest_Antwort();
if ($data['Antwort']) {
$form->saveInto($Antwort);
if ($data['Art'] == 'Mechanics') {
$Antwort->Antwort = $Ant;
}
$Antwort->SchreiberID = Member::currentUserID();
$Antwort->FrageID = $data['ID'];
$Antwort->write();
}
$VID = $data['VortestID'];
if ($data['Aktion'] == 'AlleFragen') {
$this->redirect('/vortest/AlleFragen/' . $VID . '#' . $data['FrageNr']);
} elseif ($data['Aktion'] == 'Einzelfrage') {
$this->redirect('/vortest/Einzelfrage/' . $VID);
} else {
$this->redirect('/vortest/Test/' . $VID.'#' . $data['FrageNr']);
}
}
It works when I change the $ID to a number in this line $Nummer = Vortest_Fragen::get()->byID($ID);
When I don't change it I get the following error:
[Recoverable Error] Object of class SS_HTTPRequest could not be converted to string
How do I fix this problem?

Answer 1

Althought it is not clearly documented, Silverstripe secretly passes a request argument to and form methods on a controller. Your $ID argument is actually not what you think it is, you will find it is actually an SS_HTTPRequest object that Silverstripe has passed (without you realising).
To fix this, change the first line:
public function AntwortForm($ID) {
To:
public function AntwortForm($request, $ID) {
And make sure you update anywhere that you call this method :-)