This document needs an example.

People come here to learn how to use features they are not familiar with. Without sample code, or examples of correct use it is worse than useless as it provides false hope and wastes time.

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#### Document Details

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* ID: a138cc59-ab8c-7b92-f46e-cd7ee36cf5ce
* Version Independent ID: 4c287363-1589-e171-8b7c-15107e7b465c
* Content: [OptionalAttribute Class (System.Runtime.InteropServices)](https://docs.microsoft.com/en-us/dotnet/api/system.runtime.interopservices.optionalattribute?view=netframework-4.7.2)
* Content Source: [xml/System.Runtime.InteropServices/OptionalAttribute.xml](https://github.com/dotnet/dotnet-api-docs/blob/master/xml/System.Runtime.InteropServices/OptionalAttribute.xml)
* Product: **dotnet-api**
* GitHub Login: @rpetrusha
* Microsoft Alias: **ronpet**