ZF2 TableGateway 如何获取主键 [英] ZF2 TableGateway how to get Primary key

问题描述

我正在尝试使用 MetadataFetature 确定表的主键.但是，数据在受保护的 $sharedData 内，没有任何访问方法.如何访问它们?我是否创建新类只是为了添加getPrimary"方法?

I'm trying to determine primary key of table using MetadataFetature. However, the data are within protected $sharedData without any access method. How to acceess them ? Do I have create new class just to add "getPrimary" method ?

在 AbstractTableGateway 子项中:

Within AbstractTableGateway child:

$metadata = $this->getFeatureSet()->getFeatureByClassName('Zend\Db\TableGateway\Feature\MetadataFeature');
        die(vardump($this->sharedData));

得到

Invalid magic property access in Zend\Db\TableGateway\AbstractTableGateway::__get()

推荐答案

你只需要声明一个 FeatureSet 的后代，以及一个 MetadataFeature 的后代.

You just have to declare a descendant of FeatureSet, and a descendant of MetadataFeature.

在您自己的FeatureSet中，覆盖函数canCallMagicGet.这是我如何做到的一个例子

In your own FeatureSet, override function canCallMagicGet. Here's an example of how I did it

public function canCallMagicGet($property)
{
    if ($property == 'metadata'){
        $result = $this->getMetadataFeature();          
        return ($result!==FALSE);
    }
    else return parent::canCallMagicGet($property);        
}

在我的例子中，getMetadataFeature 返回在从 FeatureSet 类继承的受保护属性 $features 中找到的第一个 MetadataFeature 实例 (instanceof).

In my case, getMetadataFeature return first occurrence of MetadataFeature instance (instanceof) found in protected property $features inherited from the FeatureSet class.

您也可以覆盖第二种方法，callMagicGet.下面是一个示例:

You may also override this second method, callMagicGet. Here's an example how:

public function callMagicGet($property)
{        
    if ($property == 'metadata'){
        $metadataFeature = $this->getMetadataFeature();            
        return $metadataFeature->metadata;
    }
    else
        return parent::callMagicGet($property);
}

最后，您可以在自己的 MetadataFeature 中声明一个魔法方法 __get.您的 __get 可能会直接从受保护的属性 $sharedData 返回 metadata.

Finally you can declare a magic method __get in your own MetadataFeature. Your __get may return metadata directly from protected property $sharedData.

总而言之，一旦您声明了自己的FeatureSet 和MetadataFeature 后代，您就可以使用它们代替当前的后代.然后你也许可以打电话

In conclusion, once you have declared your own FeatureSet and MetadataFeature descendants, you may use them instead of current ones. Then you may be able to call

$tableGatewayInstance->metadata

您可以使用MetadataFeature收集的元数据.

and the metadata collected by MetadataFeature will be available to you.

干杯

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