Applied to a type or field?

The Remarks section states that this attribute can be "applied to types, properties, fields, methods, and method parameters", then explains some cases, but not the types nor the field ones.
It would be beneficial to explain both these cases too, as they are not obvious.

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#### Document Details

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* ID: 11dfc639-e939-8944-28d6-9c82b53b0676
* Version Independent ID: cf71b269-876f-c64d-72fb-23fc83a9b8c9
* Content: [CustomValidationAttribute Class (System.ComponentModel.DataAnnotations)](https://docs.microsoft.com/en-us/dotnet/api/system.componentmodel.dataannotations.customvalidationattribute?view=netframework-4.7.2#remarks)
* Content Source: [xml/System.ComponentModel.DataAnnotations/CustomValidationAttribute.xml](https://github.com/dotnet/dotnet-api-docs/blob/master/xml/System.ComponentModel.DataAnnotations/CustomValidationAttribute.xml)
* Product: **.net**
* GitHub Login: @dotnet-bot
* Microsoft Alias: **riande**