Silverstripe returning a populated form via controller

问题

I am trying to figure out the correct way of returning back a form that is pre-populated with data from the database. Let me show you how I am doing it right now:

TeamsPage:

<?php
class TeamsPage extends Page {
  private static $has_many = array (
    'Teams' => 'Team',
  );
  public function getCMSFields() {
    $fields = parent::getCMSFields();
    $fields->addFieldToTab('Root.Teams', GridField::create(
        'Teams',
        'Teams on this page',
        $this->Teams(),
        GridFieldConfig_RecordEditor::create()
    ));
    return $fields;
  }
}
class TeamsPage_Controller extends Page_Controller {
  private static $allowed_actions = array (
    'show', 'edit', 'EditTeamForm'
  );

  public function EditTeamForm($teamId){
    $fields = new FieldList(
        new TextField('TeamName'),
        new TextareaField('TeamDescription')
    );
    $actions = new FieldList(
        new FormAction('EditTeam', 'Save Changes')
    );
    $requiredFields = new RequiredFields(array('TeamName','TeamDescription'));
    $form = new Form($this, 'EditTeamForm', $fields, $actions, $requiredFields);
    $form->setFormMethod('POST', true);

    $data = Session::get("FormData.{$form->getName()}.data");
    $team = Team::get()->byID($teamId);
    return $data ? $form->loadDataFrom($data) : $form->loadDataFrom($team);
  }

  public function show(SS_HTTPRequest $request) {
    $team = Team::get()->byID($request->param('ID'));

    if(!$team) {
        return $this->httpError(404,'That team could not be found');
    }

    return array (
        'Team' => $team
    );
  }

  public function edit(SS_HTTPRequest $request){
    $team = Team::get()->byID($request->param('ID'));

    if(!$team) {
        return $this->httpError(404,'That team could not be found');
    }

    return array (
        'Team' => $team
    );
  }
}

Team:

<?php
class Team extends DataObject {
  private static $db = array(
    'TeamCaptain' => 'Int',
    'TeamName' => 'Varchar',
    'TeamDescription' => 'Text'
  );
  private static $has_one = array (
    'Photo' => 'Image',
    'TeamsPage' => 'TeamsPage'
  );
  private static $summary_fields = array (
    'GridThumbnail' => '',
    'TeamCaptain' => 'Team Captain',
    'TeamName' => 'TeamName',
    'TeamDescription' => 'Team Description',
  );
  public function getGridThumbnail() {
    if($this->Photo()->exists()) {
        return $this->Photo()->SetWidth(100);
    }
    return '(no image)';
  }
  public function getCMSFields() {
    $fields = FieldList::create(
        TextField::create('TeamCaptain'),
        TextField::create('TeamName'),
        TextareaField::create('TeamDescription'),
        $uploader = UploadField::create('Photo')
    );
    $uploader->setFolderName('teams-photos');
    $uploader->getValidator()->setAllowedExtensions(array(
        'png','gif','jpeg','jpg'
    ));
    return $fields;
  }

  public function Link() {
    return $this->TeamsPage()->Link('show/'.$this->ID);
  }
}

TeamsPage_edit.ss

<% if GetMember() %>
  Welcome $getMember.FirstName<br />
  $EditTeamForm($Team.ID)
  <a href="home">Back to Home</a>
<% else %>
  $GoToLogin()
<% end_if %>

As you can see in my controller I am returning a $Team that I don't fully understand how it works. In my template I use $Team.ID and I am trying to figure out if that value comes from me returning array of Teams or somehow else. The other thing I am trying to understand is why do I not return a Form here, why do I have to have a sepparate function to create that form and have to call it as such in the template. The last problem that I see here is that I am querying the database twice for the same information.

What I am asking in the end is If anyone could show me what would be the proper way to achieve what I am doing. I'm sure it has been done many times, but I could not find a single example anywhere on the internet of how to use edit forms. I have found how to use show action and return bunch of results, but nothing in combination with the forms.

回答1:

I suggest simply doing the following (these are additions to your code, not a complete class):

class TeamPage_Controller extends Page_Controller {
    protected $currentTeam;

    protected function getCurrentTeam() {
        if (!isset($this->currentTeam)) {
            $teamID = $this->getRequest()->param('ID') ?: $this->getRequest()->postVar('ID');
            $this->currentTeam = $teamID ? Team::get()->byID($teamID) : null;
        }
        return $this->currentTeam;
    }

    public function EditTeamForm() {
         $team = $this->getCurrentTeam();             
         // You'll want to add a HiddenField with the ID if $team is not null
         // everything else is the same
    }

    // NOTE: I would suggest you call this something else
    // SS convention would be "doSaveTeam" - it should be whatever your FormAction is called though
    public function EditTeam($data, $form) {
        $team = $this->getCurrentTeam();
        // Save and redirect
    }

    public function edit(SS_HTTPRequest $request){
        $team = $this->getCurrentTeam();
        // Blah blah blah
    }
}

来源：https://stackoverflow.com/questions/32742165/silverstripe-returning-a-populated-form-via-controller