We are in the process of migrating a big toolset of ours from umbraco version 7 to version 8 . In some places we were using the PreValueField attribute and overriding some of the PreValueEditor methods for custom property editors.

However, after upgrading to 8 the PreValueEditor class is no longer available and the PreValueField attributes are gone - what should they be replaced with? Couldn't find anything relating to them in the Version 8 change log.