IDbSet<TEntity>.Attach(TEntity) Method

Reference

Definition

Namespace:: System.Data.Entity

Assembly:: EntityFramework.dll

Important

Some information relates to prerelease product that may be substantially modified before it’s released. Microsoft makes no warranties, express or implied, with respect to the information provided here.

Attaches the given entity to the context underlying the set. That is, the entity is placed into the context in the Unchanged state, just as if it had been read from the database.

public TEntity Attach (TEntity entity);

abstract member Attach : 'Entity -> 'Entity

Public Function Attach (entity As TEntity) As TEntity

Parameters

entity: TEntity

The entity to attach.

Returns

TEntity

The entity.

Remarks

Attach is used to repopulate a context with an entity that is known to already exist in the database. SaveChanges will therefore not attempt to insert an attached entity into the database because it is assumed to already be there. Note that entities that are already in the context in some other state will have their state set to Unchanged. Attach is a no-op if the entity is already in the context in the Unchanged state.

Applies to