NuGet Package: DevExpress.ExpressApp
An ErrorMessages object which is used to access the messages about currently broken Validation Rules.
Validation Rules can be applied to a business class. When these Rules are broken, the ErrorMessages collection of the List Editor that represents this class’ object(s) is populated with the error messages.
Generally, you do not need to use this property. Although, you may use it in a custom feature for the Validation System.