Symfony2 Embedded表单删除按钮功能

Question

I have created an embedded form in Symfony2 which has many "Employees" in one "Department". Now, the Addition of many employees with their "Firstname" and "Lastname" is working fine on the "Department" form (I have used jQuery for this purpose). I want the "Delete" button functionality on the form, which I am unable to figure out. Can anyone help me with the delete button function?

DepartmentType.php

<?php

namespace InstituteEvents\FormBundle\Form;

use Symfony\Component\Form\AbstractType;
use Symfony\Component\Form\FormBuilderInterface;
use Symfony\Component\OptionsResolver\OptionsResolverInterface;

class DepartmentType extends AbstractType
{
/**
 * @param FormBuilderInterface $builder
 * @param array $options
 */
 public function buildForm(FormBuilderInterface $builder, array $options)
{
    $builder
        ->add('name')
        ->add('employees','collection', array(
            'type' => new EmployeeType(),
            'prototype' => true,
            'allow_add' => true,
            'by_reference' =>false
         ))    
    ;
}

/**
 * @param OptionsResolverInterface $resolver
 */
public function setDefaultOptions(OptionsResolverInterface $resolver)
{
    $resolver->setDefaults(array(
        'data_class' => 'InstituteEvents\FormBundle\Entity\Department'
    ));
}

/**
 * @return string
 */
public function getName()
{
    return 'department';
}
}

EmployeeType.php

<?php

namespace InstituteEvents\FormBundle\Form;

use Symfony\Component\Form\AbstractType;
use Symfony\Component\Form\FormBuilderInterface;
use Symfony\Component\OptionsResolver\OptionsResolverInterface;

class EmployeeType extends AbstractType
{
/**
 * @param FormBuilderInterface $builder
 * @param array $options
 */
public function buildForm(FormBuilderInterface $builder, array $options)
{
    $builder
        ->add('firstname')
        ->add('lastname')
    ;
}

/**
 * @param OptionsResolverInterface $resolver
 */
public function setDefaultOptions(OptionsResolverInterface $resolver)
{
    $resolver->setDefaults(array(
        'data_class' => 'InstituteEvents\FormBundle\Entity\Employee'
    ));
}

/**
 * @return string
 */
public function getName()
{
    return 'employee';
}
}

index.html.twig - This file contains the "add employees" button functionality in jQuery. Here I want the "delete employees" button + functionality. I don't know javascript or jQuery properly, so I need help in adding the "delete employees" button + the code for it.

<script src="http://code.jquery.com/jquery-1.9.1.min.js"></script>
<script>
$(function() {
    var index = 0;
    var prototype = $('ul.form-employees').data('prototype');
    $('#form-employee-btn').on('click', function() { 
        var newForm = prototype.replace(/__name__/g, index++);
        var newLi = $('<li></li>');

        newLi.append(newForm);
        $(this).before(newLi);
    });
});
</script>    
<form method = "post">
{{ form_label(form.name, 'Department Name') }}
{{ form_widget(form.name) }}

<ul class="form-employees" data-prototype = "{{ form_widget(form.employees.vars.prototype)|e }}">
   <input id="form-employee-btn" type="button" value="Add Employees"/>
</ul>

   {{ form_widget(form._token) }}

<input type="submit" value="Submit"/>

</form>

Answer 1

Following the instructions found in the docs :

In your DepartmentType form class, set the EmployeeType collection's allow_delete attribute to true :

    $builder
        ->add('name')
        ->add('employees','collection', array(
            'type' => new EmployeeType(),
            'prototype' => true,
            'allow_add' => true,
            'allow_delete' => true,//add this
            'by_reference' =>false
         )
    );

Next, add the delete button (either through the builder in your EmployeeType form ( ->add('delete', 'button') ), or manually (using JS in the tempalte). Then attach an event listener to the form. Assuming you've added the delete button like so:

//EmployeeType:
$builder->add('delete', 'button', ['attr' => ['class' => 'delete-employee']]);

If you're adding the buttons using JS in the view, then this code should do the trick:

$('#department-form-selector').children('employee-form-selector').each(function(i)
{
    $(this).append('<button name="delete' + i + '" class="delete-employee">Delete</button>');
});

When the buttons have been added (or are about to be added), attach a listener using jQ. The buttons needn't be in the DOM at this stage, because we're using event delegation, instead of direct binding:

$('#department-form-selector').on('click', '.delete-employee', function()
{
    $(this).closest('form').delete();//remove element
    //optionally submit department form via AJAX call to persist the delete
    return false;//stop event
});

Now, to handle the form (assuming the entities are set up properly):

//in the controller that handles the form:
if ($form->isValid())
{
    //1 => we need to query for the data in the DB, so we know what to delete
    $current = $service->getCurrentDepartmentWithEmployees();
    //get the current employees, that need to be updated
    $oldEmployees = new ArrayCollection();
    foreach ($current->getEmployees() as $employee)
        $oldEmployees->add($employee);
    //2 => get the form data
    $department = $form->getData();
    //3 => check if one or more eployees were deleted
    foreach ($oldEmployees as $employee)
    {
        if (!$department->getEmployees()->contains($employee))
        {//employee was removed, update entity/entities
            $current->getEmployees()->removeElement($employee);
            //depending on the relations you've specified:
            $employee->setDepartment(null);
            $em->persist($employee);
            $em->persist($current);
        }
    }
    $em->flush();
}

Note that this code is untested . It's the basic flow of a worst-case-scenario deletion (bi-directional, one to many relation that is inversed, but no ondelete cascade restrictions have been set).
Using this code as a reference, you should be able to work it out, though