Validation of domain objects and displaying validation results in a view

Question

I have a client -> service -> server, architecture, and I want to enter confirmation.

I have dtos that are passed through a service and converted to domain objects on the server.

Tell me if the user enters a value and I need to check this value against the database to see if it exists, and if so, return an error and highlight the field, how would I best do this?

Answer 1

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IDataErrorInfo .NET, Windows Forms, WPF - .

Answer 2

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