小编arn*_*rno的帖子

我有一个带有联系人列表的表单.我想在提交后显示所选联系人值字段"名字" .我的问题是该字段出现但我无法设置好的数据,该字段始终保持为空.

public function buildForm(FormBuilderInterface $builder, array $options)
{

    $builder
        ->add('contacts', ChoiceType::class, [
            'label'       => 'Contact',
            'placeholder' => 'Choose a contact',
            'choices'     => $this->getContacts(),
            'mapped'      => false,
        ])
        ->setMethod('POST')
    ;

    $builder->get('contacts')->addEventListener(FormEvents::POST_SUBMIT, function (FormEvent $event) {

        $contactId     = $event->getData();
        $parentForm    = $event->getForm()->getParent();

        $contactEntity = $exampleEm->getrepository(Contact::class)->find($contactId);
        $firstName     = $contactEntity->getFirstName();

        // where can I set the 'contactFirstname' data ?

        $parentForm
            ->add('contactFirstname', TextType::class, [
                'label' => 'First name',
            ]);
    })
    ;
}

如何输入正确的数据以使字段显示为预填？

编辑: 我找到了一个方法,但并不可怕:

$parentForm
            ->add('contactFirstname', TextType::class, [
                'label'         => 'First …

如何在所有网站上安装调试栏？
在管理方面我激活了debug mode,但Symfony调试条只在"模块"部分可见.
是否可以在所有网站上显示它,如运输部分？

我对composer有问题，它一直运行良好，但现在不想……
这是一个简单composer install命令的结果：

bob@SRV04:~/testdir$ composer install
Loading composer repositories with package information
Updating dependencies
Package operations: 44 installs, 0 updates, 0 removals
  - Installing psr/container (1.0.0): The following exception is caused by a 
lack of memory or swap, or not having swap configured
Check https://getcomposer.org/doc/articles/troubleshooting.md#proc-open- 
fork-failed-errors for details

PHP Warning:  proc_open(): fork failed - Cannot allocate memory in 
phar:///bin/composer/vendor/symfony/console/Application.php on line 952

Warning: proc_open(): fork failed - Cannot allocate memory in 
phar:///bin/composer/vendor/symfony/console/Application.php on line 952

[ErrorException] …

有没有办法区分2 ArrayCollection？（例如array_diff）

今天我循环第一个，检查$ it-> contains（）是否匹配，但是我认为它可以重构。