Class ReferenceCollectionBuilder<TPrincipalEntity, TDependentEntity>

Namespace

Microsoft.EntityFrameworkCore.Metadata.Builders

Assembly

Microsoft.EntityFrameworkCore.dll

Provides a simple API for configuring a one-to-many relationship.

public class ReferenceCollectionBuilder<TPrincipalEntity, TDependentEntity> : ReferenceCollectionBuilder, IInfrastructure<IConventionForeignKeyBuilder> where TPrincipalEntity : class where TDependentEntity : class

Type Parameters

TPrincipalEntity

The principal entity type in this relationship.

TDependentEntity

The dependent entity type in this relationship.

Inheritance

object

RelationshipBuilderBase

ReferenceCollectionBuilder

ReferenceCollectionBuilder<TPrincipalEntity, TDependentEntity>

Implements

IInfrastructure<IConventionForeignKeyBuilder>

Inherited Members

ReferenceCollectionBuilder.HasForeignKeyBuilder(IReadOnlyList<string>)

ReferenceCollectionBuilder.HasForeignKeyBuilder(IReadOnlyList<MemberInfo>)

ReferenceCollectionBuilder.HasPrincipalKeyBuilder(IReadOnlyList<string>)

ReferenceCollectionBuilder.HasPrincipalKeyBuilder(IReadOnlyList<MemberInfo>)

RelationshipBuilderBase.PrincipalEntityType

RelationshipBuilderBase.DependentEntityType

RelationshipBuilderBase.Builder

RelationshipBuilderBase.Metadata

object.GetType()

object.MemberwiseClone()

object.ToString()

object.Equals(object)

object.Equals(object, object)

object.ReferenceEquals(object, object)

object.GetHashCode()

Extension Methods

AccessorExtensions.GetInfrastructure<T>(IInfrastructure<T>)

Remarks

Instances of this class are returned from methods when using the ModelBuilder API and it is not designed to be directly constructed in your application code.

See Modeling entity types and relationships for more information and examples.

Constructors

ReferenceCollectionBuilder(IMutableEntityType, IMutableEntityType, IMutableForeignKey)

This is an internal API that supports the Entity Framework Core infrastructure and not subject to the same compatibility standards as public APIs. It may be changed or removed without notice in any release. You should only use it directly in your code with extreme caution and knowing that doing so can result in application failures when updating to a new Entity Framework Core release.

[EntityFrameworkInternal]
public ReferenceCollectionBuilder(IMutableEntityType principalEntityType, IMutableEntityType dependentEntityType, IMutableForeignKey foreignKey)

Parameters

principalEntityType IMutableEntityType

dependentEntityType IMutableEntityType

foreignKey IMutableForeignKey

ReferenceCollectionBuilder(InternalForeignKeyBuilder, ReferenceCollectionBuilder, bool, bool, bool)

This is an internal API that supports the Entity Framework Core infrastructure and not subject to the same compatibility standards as public APIs. It may be changed or removed without notice in any release. You should only use it directly in your code with extreme caution and knowing that doing so can result in application failures when updating to a new Entity Framework Core release.

[EntityFrameworkInternal]
protected ReferenceCollectionBuilder(InternalForeignKeyBuilder builder, ReferenceCollectionBuilder oldBuilder, bool foreignKeySet = false, bool principalKeySet = false, bool requiredSet = false)

Parameters

builder InternalForeignKeyBuilder

oldBuilder ReferenceCollectionBuilder

foreignKeySet bool

principalKeySet bool

requiredSet bool

Methods

HasAnnotation(string, object?)

Adds or updates an annotation on the relationship. If an annotation with the key specified in annotation already exists its value will be updated.

public virtual ReferenceCollectionBuilder<TPrincipalEntity, TDependentEntity> HasAnnotation(string annotation, object? value)

Parameters

annotation string

The key of the annotation to be added or updated.

value object

The value to be stored in the annotation.

Returns

ReferenceCollectionBuilder<TPrincipalEntity, TDependentEntity>

The same builder instance so that multiple configuration calls can be chained.

HasForeignKey(Expression<Func<TDependentEntity, object?>>)

Configures the property(s) to use as the foreign key for this relationship.

public virtual ReferenceCollectionBuilder<TPrincipalEntity, TDependentEntity> HasForeignKey(Expression<Func<TDependentEntity, object?>> foreignKeyExpression)

Parameters

foreignKeyExpression Expression<Func<TDependentEntity, object>>

A lambda expression representing the foreign key property(s) (post => post.BlogId).

If the foreign key is made up of multiple properties then specify an anonymous type including the properties (comment => new { comment.BlogId, comment.PostTitle }). The order specified should match the order of corresponding properties in HasPrincipalKey(Expression<Func<TPrincipalEntity, object?>>).

Returns

ReferenceCollectionBuilder<TPrincipalEntity, TDependentEntity>

The same builder instance so that multiple configuration calls can be chained.

Remarks

If HasPrincipalKey(Expression<Func<TPrincipalEntity, object?>>) is not specified, then an attempt will be made to match the data type and order of foreign key properties against the primary key of the principal entity type. If they do not match, new shadow state properties that form a unique index will be added to the principal entity type to serve as the reference key. A shadow state property is one that does not have a corresponding property in the entity class. The current value for the property is stored in the ChangeTracker rather than being stored in instances of the entity class.

HasForeignKey(params string[])

Configures the property(s) to use as the foreign key for this relationship.

public virtual ReferenceCollectionBuilder<TPrincipalEntity, TDependentEntity> HasForeignKey(params string[] foreignKeyPropertyNames)

Parameters

foreignKeyPropertyNames string[]

The name(s) of the foreign key property(s).

Returns

ReferenceCollectionBuilder<TPrincipalEntity, TDependentEntity>

The same builder instance so that multiple configuration calls can be chained.

Remarks

If the specified property name(s) do not exist on the entity type then a new shadow state property(s) will be added to serve as the foreign key. A shadow state property is one that does not have a corresponding property in the entity class. The current value for the property is stored in the ChangeTracker rather than being stored in instances of the entity class.

If HasPrincipalKey(Expression<Func<TPrincipalEntity, object?>>) is not specified, then an attempt will be made to match the data type and order of foreign key properties against the primary key of the principal entity type. If they do not match, new shadow state properties that form a unique index will be added to the principal entity type to serve as the reference key.

HasPrincipalKey(Expression<Func<TPrincipalEntity, object?>>)

Configures the unique property(s) that this relationship targets. Typically you would only call this method if you want to use a property(s) other than the primary key as the principal property(s). If the specified property(s) is not already a unique constraint (or the primary key) then a new unique constraint will be introduced.

public virtual ReferenceCollectionBuilder<TPrincipalEntity, TDependentEntity> HasPrincipalKey(Expression<Func<TPrincipalEntity, object?>> keyExpression)

Parameters

keyExpression Expression<Func<TPrincipalEntity, object>>

A lambda expression representing the referenced key property(s) (blog => blog.BlogId).

If the principal key is made up of multiple properties then specify an anonymous type including the properties (t => new { t.Id1, t.Id2 }). The order specified should match the order of corresponding properties in HasForeignKey(Expression<Func<TDependentEntity, object?>>).

Returns

ReferenceCollectionBuilder<TPrincipalEntity, TDependentEntity>

The same builder instance so that multiple configuration calls can be chained.

HasPrincipalKey(params string[])

Configures the unique property(s) that this relationship targets. Typically you would only call this method if you want to use a property(s) other than the primary key as the principal property(s). If the specified property(s) is not already a unique constraint (or the primary key) then a new unique constraint will be introduced.

public virtual ReferenceCollectionBuilder<TPrincipalEntity, TDependentEntity> HasPrincipalKey(params string[] keyPropertyNames)

Parameters

keyPropertyNames string[]

The name(s) of the referenced key property(s).

Returns

ReferenceCollectionBuilder<TPrincipalEntity, TDependentEntity>

The same builder instance so that multiple configuration calls can be chained.

IsRequired(bool)

Configures whether this is a required relationship (i.e. whether the foreign key property(s) can be assigned null).

public virtual ReferenceCollectionBuilder<TPrincipalEntity, TDependentEntity> IsRequired(bool required = true)

Parameters

required bool

A value indicating whether this is a required relationship.

Returns

ReferenceCollectionBuilder<TPrincipalEntity, TDependentEntity>

The same builder instance so that multiple configuration calls can be chained.

OnDelete(DeleteBehavior)

Configures the operation applied to dependent entities in the relationship when the principal is deleted or the relationship is severed.

public virtual ReferenceCollectionBuilder<TPrincipalEntity, TDependentEntity> OnDelete(DeleteBehavior deleteBehavior)

Parameters

deleteBehavior DeleteBehavior

The action to perform.

Returns

ReferenceCollectionBuilder<TPrincipalEntity, TDependentEntity>

The same builder instance so that multiple configuration calls can be chained.