执行'；时发生异常；INSERT INTO事件(user_id，ET1，ET2）值(?，?，?）'；带有pa

我正在尝试从默认控制器内部创建表单。我希望主页中两个下拉列表的值都存储在事件表的ET1和ET2列中，我可以做到这一点。但是，我希望登录用户的user_id也应该存储在事件表格的user_ids列中。在尝试这样做的时候，它给了我一个错误：

执行"INSERT INTO事件（user_id，ET1，ET2）VALUES（？，？，？）'with params[null，2，3]：SQLSTATE[23000]：完整性约束冲突：1048列"user_id"不能为空

这是我的defaultcontroller 代码

<?php
namespace AppBundle'Controller;
use AppBundle'Entity'events;
//use AppBundle'Entity'eventtype;
use AppBundle'Entity'users;
use Sensio'Bundle'FrameworkExtraBundle'Configuration'Route;
use Symfony'Bundle'FrameworkBundle'Controller'Controller;
use Symfony'Component'HttpFoundation'Request;
use Symfony'Component'HttpFoundation'Response;
use Symfony'Component'Form'Extension'Core'Type'SubmitType;
use Symfony'Component'Form'Extension'Core'Type'ChoiceType;
class DefaultController extends Controller {
    /**
     * @Route("/home", name="homepage")
     */
    public function indexAction(Request $request) {
        $events = new events();
        $form = $this->createFormBuilder($events)
                ->add('eT1', ChoiceType::class, array(
                    'choices' => array(
                        'Poker' => 1,
                        'Chess' => 2,
                        'Cricket' => 3,
                        'Marbles' => 4,
                        'Football' => 5,
                    ),
                    'choices_as_values' => true,
                ))
                ->add('eT2', ChoiceType::class, array(
                    'choices' => array(
                        'Poker' => 1,
                        'Chess' => 2,
                        'Cricket' => 3,
                        'Marbles' => 4,
                        'Football' => 5,
                    ),
                    'choices_as_values' => true,
                ))
                ->add('save', SubmitType::class, array('label' => 'Submit'))
                ->getForm();
        if ($request->isMethod('POST')) {
            $form->submit($request);
            if ($form->isValid()) {
                // perform some action, eg. persisting the data to database...
                $user = $this->container->get('security.context')->getToken()->getUser();
                $id = $user->getId();
//               var_dump($id);
//                exit;
                $events->setuserID($id);

                $em = $this->getDoctrine()->getManager();
                // tells Doctrine you want to (eventually) save the Product (no queries yet)
                $em->persist($events);
                // actually executes the queries (i.e. the INSERT query)
                $em->flush();
                return $this->redirectToRoute('homepage');
            }
        }
        return $this->render('default/index.html.twig', array(
                    'form' => $form->createView(),
        ));
    }

以下是用户的etity

<?php
namespace AppBundle'Entity;
use FOS'UserBundle'Model'User as BaseUser;
use Doctrine'ORM'Mapping as ORM;
use Symfony'Component'Validator'Constraints as Assert;
use Doctrine'Common'Collections'ArrayCollection;
/**
 * users
 *
 * @ORM'Table(name="users")
 * @ORM'Entity(repositoryClass="AppBundle'Repository'usersRepository")
 */
class users extends BaseUser
{
    /**
     * @ORM'Column(name="id", type="integer")
     * @ORM'Id
     * @ORM'GeneratedValue(strategy="AUTO")
     */
    protected $id;
        /**
     * Get id
     * @return integer 
     */
    public function getId()
    {
        return $this->id;
    }
    /**
     * @ORM'OneToMany(targetEntity="events", mappedBy="users")
     */
    protected $multiEvents;

    public function __construct()
    {
        parent::__construct();
        $this->multiEvents = new ArrayCollection();   
         }
    }

以下是事件实体

<?php
namespace AppBundle'Entity;
use Doctrine'ORM'Mapping as ORM;
/**
 * events
 *
 * @ORM'Table(name="events")
 * @ORM'Entity(repositoryClass="AppBundle'Repository'eventsRepository")
 */
class events
{
    /**
     * @var int
     *
     * @ORM'Column(name="id", type="integer")
     * @ORM'Id
     * @ORM'GeneratedValue(strategy="AUTO")
     */
    protected $id;
    /**
     * @var int
     *
     * @ORM'Column(name="user_id", type="integer")
     */
    protected $user_id;
    /**
     * @var int
     *
     * @ORM'Column(name="ET1", type="integer")
     */
    protected $eT1;
    /**
     * @var int
     *
     * @ORM'Column(name="ET2", type="integer")
     */
    protected $eT2;
    /**
     * @ORM'ManyToOne(targetEntity="users", inversedBy="multievents")
     * @ORM'JoinColumn(name="user_id", referencedColumnName="id")
     */
    private $singleUser;

    /**
     * Get id
     *
     * @return integer 
     */
    public function getId()
    {
        return $this->id;
    }
    /**
     * Get user_id
     *
     * @return integer 
     */
    public function getuser_id()
    {
        return $this->user_id;
    }
    /**
     * Set user_id
     *
     * @param integer $user_id
     * @return events
     */
    public function setuserID($user_id)
    {
        $this->user_id = $user_id;
        return $this;
    }
    /**
     * Set eT1
     *
     * @param integer $eT1
     * @return events
     */
    public function setET1($eT1)
    {
        $this->eT1 = $eT1;
        return $this;
    }
    /**
     * Get eT1
     *
     * @return integer 
     */
    public function getET1()
    {
        return $this->eT1;
    }
    /**
     * Set eT2
     *
     * @param integer $eT2
     * @return events
     */
    public function setET2($eT2)
    {
        $this->eT2 = $eT2;
        return $this;
    }
    /**
     * Get eT2
     *
     * @return integer 
     */
    public function getET2()
    {
        return $this->eT2;
    }
}