poc form SDK (extends to form)

sources/DI/Form/Transformer/ExternalKeyTransformer.php

@@ -0,0 +1,42 @@
+<?php
+
+namespace Combodo\iTop\DI\Form\Transformer;
+
+use Exception;
+use MetaModel;
+use Symfony\Component\Form\DataTransformerInterface;
+
+/**
+ * Transform external key ref to external key name representation.
+ */
+class ExternalKeyTransformer implements DataTransformerInterface
+{
+
+	/** @var string $sObjectClass */
+	private string $sObjectClass;
+
+	/**
+	 * @param string $sObjectClass
+	 */
+	public function __construct(string $sObjectClass)
+	{
+		$this->sObjectClass = $sObjectClass;
+	}
+
+	/** @inheritdoc  */
+	public function transform($value)
+	{
+		try{
+			return MetaModel::GetObject($this->sObjectClass, $value)->GetName();
+		}
+		catch(Exception $e){
+			return null;
+		}
+	}
+
+	/** @inheritdoc  */
+	public function reverseTransform($value)
+	{
+		return $value;
+	}
+}