You are implementing an application that uses Entity Framework. You load an Order entity by querying the Orders property of a strongly typed ObjectContext. After you modify the Order entity, you need to compare a current property value with the cached original property value.

What should you do?

The ObjectStateManager class maintains object state and identity management for entity type instances and relationship instances. You can access its OriginalValue and ModifiedValues properties to compare object properties for attached entities only. An entity that is created by deserializing a serialized representation is detached.

The ObjectContext.Attach method attaches an object or object graph to the object context when the object has an entity key. It does not retrieve cached original values.