DbContext.Attach Method

Definition

Overloads

Attach(Object)

Begins tracking the given entity and entries reachable from the given entity using the Unchanged state by default, but see below for cases when a different state will be used.

Generally, no database interaction will be performed until SaveChanges() is called.

A recursive search of the navigation properties will be performed to find reachable entities that are not already being tracked by the context. All entities found will be tracked by the context.

For entity types with generated keys if an entity has its primary key value set then it will be tracked in the Unchanged state. If the primary key value is not set then it will be tracked in the Added state. This helps ensure only new entities will be inserted. An entity is considered to have its primary key value set if the primary key property is set to anything other than the CLR default for the property type.

For entity types without generated keys, the state set is always Unchanged.

Use State to set the state of only a single entity.

Attach<TEntity>(TEntity)

Begins tracking the given entity and entries reachable from the given entity using the Unchanged state by default, but see below for cases when a different state will be used.

Generally, no database interaction will be performed until SaveChanges() is called.

A recursive search of the navigation properties will be performed to find reachable entities that are not already being tracked by the context. All entities found will be tracked by the context.

For entity types with generated keys if an entity has its primary key value set then it will be tracked in the Unchanged state. If the primary key value is not set then it will be tracked in the Added state. This helps ensure only new entities will be inserted. An entity is considered to have its primary key value set if the primary key property is set to anything other than the CLR default for the property type.

For entity types without generated keys, the state set is always Unchanged.

Use State to set the state of only a single entity.

Attach(Object)

Begins tracking the given entity and entries reachable from the given entity using the Unchanged state by default, but see below for cases when a different state will be used.

Generally, no database interaction will be performed until SaveChanges() is called.

A recursive search of the navigation properties will be performed to find reachable entities that are not already being tracked by the context. All entities found will be tracked by the context.

For entity types with generated keys if an entity has its primary key value set then it will be tracked in the Unchanged state. If the primary key value is not set then it will be tracked in the Added state. This helps ensure only new entities will be inserted. An entity is considered to have its primary key value set if the primary key property is set to anything other than the CLR default for the property type.

For entity types without generated keys, the state set is always Unchanged.

Use State to set the state of only a single entity.

public virtual Microsoft.EntityFrameworkCore.ChangeTracking.EntityEntry Attach (object entity);
abstract member Attach : obj -> Microsoft.EntityFrameworkCore.ChangeTracking.EntityEntry
override this.Attach : obj -> Microsoft.EntityFrameworkCore.ChangeTracking.EntityEntry
Public Overridable Function Attach (entity As Object) As EntityEntry

Parameters

entity
Object

The entity to attach.

Returns

EntityEntry

The EntityEntry for the entity. The entry provides access to change tracking information and operations for the entity.

Applies to

Attach<TEntity>(TEntity)

Begins tracking the given entity and entries reachable from the given entity using the Unchanged state by default, but see below for cases when a different state will be used.

Generally, no database interaction will be performed until SaveChanges() is called.

A recursive search of the navigation properties will be performed to find reachable entities that are not already being tracked by the context. All entities found will be tracked by the context.

For entity types with generated keys if an entity has its primary key value set then it will be tracked in the Unchanged state. If the primary key value is not set then it will be tracked in the Added state. This helps ensure only new entities will be inserted. An entity is considered to have its primary key value set if the primary key property is set to anything other than the CLR default for the property type.

For entity types without generated keys, the state set is always Unchanged.

Use State to set the state of only a single entity.

public virtual Microsoft.EntityFrameworkCore.ChangeTracking.EntityEntry<TEntity> Attach<TEntity> (TEntity entity) where TEntity : class;
abstract member Attach : 'Entity -> Microsoft.EntityFrameworkCore.ChangeTracking.EntityEntry<'Entity (requires 'Entity : null)> (requires 'Entity : null)
override this.Attach : 'Entity -> Microsoft.EntityFrameworkCore.ChangeTracking.EntityEntry<'Entity (requires 'Entity : null)> (requires 'Entity : null)
Public Overridable Function Attach(Of TEntity As Class) (entity As TEntity) As EntityEntry(Of TEntity)

Type Parameters

TEntity

The type of the entity.

Parameters

entity
TEntity

The entity to attach.

Returns

EntityEntry<TEntity>

The EntityEntry<TEntity> for the entity. The entry provides access to change tracking information and operations for the entity.

Applies to