fixed metadata

mikeblome · mikeblome · commit 8ac558ab61c5 · 2019-05-16T09:17:49.000-07:00
diff --git a/docs/extensions/classes-and-structs-cpp-component-extensions.md b/docs/extensions/classes-and-structs-cpp-component-extensions.md
@@ -2,7 +2,7 @@
 title: "ref class and ref struct (C++/CLI and C++/CX)"
 ms.date: "05/16/2019"
 ms.topic: "reference"
-f1_keywords: "ref class"
+f1_keywords: ["ref class"]
 helpviewer_keywords: ["ref class keyword [C++]", "value class keyword [C++]", "value struct keyword [C++]", "ref struct keyword [C++]"]
 ms.assetid: 5c360764-b229-49c6-9357-66213afbc372
 ---
