级联刷新在学说中的多对多关联

Question

我是学说的新手。

我有这个实体'交易'，它与级联刷新到实体'货物'有多对多关联 （单向）

我有这段代码：

$trans = $em->getRepository('bundle:Transaction')->find($id);
$form = $this->createForm($trans);
$form->handleRequest($request);
if ($isCancel)
{
     $em->refresh($trans);
}

交易实体已被还原但货物实体未还原。 我错过了什么？

transaction.orm.xml：

<?xml version="1.0"?>
    <doctrine-mapping xmlns="http://doctrine-project.org/schemas/orm/doctrine-mapping" xsi="http://www.w3.org/2001/XMLSchema-instance" schemaLocation="http://doctrine-project.org/schemas/orm/doctrine-mapping.xsd">
      <entity name="Oss\PWORegBundle\Entity\Transaction" table="pworeg_transaction">
        <id name="id" type="integer" column="id">
          <generator strategy="IDENTITY"/>
        </id>
        <field name="transactionType" type="string" length="255" nullable="true" column="transaction_type"/>    
        <many-to-many field="goods" target-entity="Oss\PWORegBundle\Entity\Goods">
            <join-table name="transaction_goods">
                <join-columns>
                    <join-column name="tcId" referenced-column-name="id" />
                </join-columns>
                <inverse-join-columns>
                    <join-column name="goodsTechId" referenced-column-name="id" unique="true" />
                </inverse-join-columns>
            </join-table>
            <cascade>
                <cascade-persist />
                <cascade-remove />
                <cascade-refresh />
            </cascade>
        </many-to-many>
        <field name="status" type="string" length="3" nullable="true" column="status"/>    
      </entity>
    </doctrine-mapping>

goods.orm.xml：

<?xml version="1.0"?>
    <doctrine-mapping xmlns="http://doctrine-project.org/schemas/orm/doctrine-mapping" xsi="http://www.w3.org/2001/XMLSchema-instance" schemaLocation="http://doctrine-project.org/schemas/orm/doctrine-mapping.xsd">
      <entity name="Oss\PWORegBundle\Entity\Goods" table="goods">
        <id name="id" type="integer" column="id">
          <generator strategy="IDENTITY"/>
        </id>
        <field name="name" type="string" length="255" nullable="true" column="name"/>
        <field name="type" type="string" length="255" nullable="true" column="type"/>
      </entity>
    </doctrine-mapping>