I am trying to establish a many-to-one relationship. The entity that represents the “many” has a navigation property pointing back to the parent entity. It looks like this:
public abstract class BaseEntity
{
/// <summary>
/// Key Field for all entities
/// </summary>
///
[Key, DatabaseGenerated(DatabaseGeneratedOption.Identity)]
public Guid Id { get; set; }
/// <summary>
/// Date entity was created
/// </summary>
public DateTime DateCreated { get; set; }
/// <summary>
/// Last date Modified
/// </summary>
public DateTime DateModified { get; set; }
/// <summary>
/// keep track of Row Version used for concurrency
/// </summary>
[Timestamp]
public Byte[] RowVersion { get; set; }
}
public abstract class Document : BaseEntity
{
#region Primitive Properties
/// <summary>
/// Boolean value to determine if Document is in an active state
/// </summary>
public bool IsActive { get; set; }
/// <summary>
/// Document comments and information
/// </summary>
[Required]
public string Description { get; set; }
#endregion
#region Navigation Properties
public ICollection<Comment> Comments { get; set; }
/// <summary>
/// FK back to User who owns document
/// </summary>
//public Guid OwnerId { get; set; }
public Guid OwnerId { get; set; }
/// <summary>
/// Navigation Back to User who owns document
/// </summary>
public User Owner { get; set; }
#endregion
}
public class Project : BaseEntity
{
public string Name { get; set; }
public string ProjectNumber { get; set; }
public string Description { get; set; }
public string CreatedBy { get; set; }
public string ModifiedBy { get; set; }
public string Currency { get; set; }
#region Navigation Properties
public virtual Address Address { get; set; }
public virtual CompanyCode CompanyCode { get; set; }
public virtual ICollection<Contact> TeamMembers { get; set; }
#endregion
}
public class Rfi : Document
{
public string Number { get; set; }
#region Navigation Properties
//This points back to a Project Entity
public virtual Guid ProjectId { get; set; }
public virtual Project Project { get; set; }
#endregion
}
So, when I insert the above entity, I am passing the ProjectId from the application into the Rfi entity (not the entire Project entity). Everything saves fine. The issue I am having is, when I pull the Rfi object back out of the database, the ProjectId is being populated, but the Project entity is null. I am using Lazy Loading, by default. Do I need to specify a navigation property on the Project entity, too? I don’t really want to. Unless, I can perform a mapping on my Rfi to accomplish this.
Update:
I assumed EF 4.1 would load my objects for me, but it seems, sometimes I need to explicitly include what objects I want to load. I am not entirely sure why. I am using a repository to query my entities. Here is the method I used to query the Rfi object:
public IQueryable<TEntity> GetQuery(Expression<Func<TEntity, bool>> predicate)
{
return _context.Set<TEntity>().AsQueryable();
}
What I ended up doing, in my Service layer I call it like this:
public Rfi FindByNumber(string number)
{
var rfi = rfiRepository.GetQuery(r => r.Number == number).Include(r => r.Project).Single;
return rfi
}
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