One or Zero to One Entity Framework Code First FluentApi

Question

1. I need to create fluentapi one or zero to one reference and have navigation properties on both of entities.

2. EntityTwo should contain simple proerty to sto

Answer 1

The only way I've come up with to handle this is, which is admittedly somewhat ugly, is creating a collection and a helper property to represent the one/zero side. Data annotations included for clarity.

public class EntityOne
{
    [Key]
    public int EntityOneId { get; set; }

    public EntityTwo EntityTwo => EntityTwoNavigation?.FirstOrDefault();
    public ICollection EntityTwoNavigation { get; set; }
}

public class EntityTwo
{
    [Key]
    public int EntityTwoId { get; set; }
    public int EntityOneId { get; set; }

    [ForeignKey("EntityOneId")]
    public EntityOne EntityOne { get; set; }
}