hasone mapping

1-1 Relationships

To configure a 1-1 relationship on an entity property use the HasOne() method.

entity.HasOne( p => p.Supplier )
    .WithForeignKey( p => p.SupplierId )
    .References<Supplier>( p => p.Id );

In the above example:

• The .HasOne() lambda expression specifies the entity relationship property.
• The .WithForeignKey() lambda expression specifies the entity foreign key property.
• The .References<>() lambda expression specifies the foreign key reference entity and (usually) primary key.

Entity Class

In your entity class use EntityReference<TEntity> to declare your 1-1 relationship properties.

    public class Product
    {
        /// <summary>
        /// Gets or sets the order id. Primary key.
        /// </summary>
        public int Id { get; set; }

        /// <summary>
        /// Gets or sets the product name.
        /// </summary>
        public string Name { get; set; }

        /// <summary>
        /// Gets or sets the product price.
        /// </summary>
        public double Price { get; set; }

        /// <summary>
        /// Gets or sets the SupplierId. Foreign key. Required.
        /// </summary>
        public int SupplierId { get; set; }

        /// <summary>
        /// Gets or sets the supplier entity. HasOne, 1-1 relationship.
        /// </summary>
        public EntityReference<Supplier> Supplier { get; set; }

        /// <summary>
        /// Gets or sets the set of product parts. HasMany, 1-many relationship.
        /// </summary>
        public EntityCollection<Part> Parts { get; set; }
    }