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Session: How to get entity etag?

When document is downloaded from server it contains various metadata information e.g. Id or current etag. Current etag is stored within metadata in session and available for each entity using GetEtagFor method from Advanced session operations.

Syntax

Etag GetEtagFor<T>(T instance);
Parameters
instance T Instance of an entity for which etag will be returned.
Return Value
ETag Returns current etag for an entity. If the instance is transient it will load document from server and attach entity and its metadata to session.

Example

Employee employee = session.Load<Employee>("employees/1");
Etag etag = session.Advanced.GetEtagFor(employee);