DbSet<TEntity>.Attach(TEntity) Method

Definition

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 virtual TEntity Attach (TEntity entity);
abstract member Attach : 'Entity -> 'Entity
override this.Attach : 'Entity -> 'Entity
Public Overridable Function Attach (entity As TEntity) As TEntity

Parameters

entity
TEntity

The entity to attach.

Returns

TEntity

The entity.

Implements

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