在 EntityFramework 中的现有行上更新或添加子记录

Question

I have an existing row in SQL called OrderLine. This links (but does not have to) OrderLineCustomFields. An OrderLine can be inserted with no OrderLineCustomFields object but could have OrderLineCustomFields at a later date. I don't receive any errors but when the OrderLine is saved, the generated column (OrderLineCustomFields_OrderLineCustomFieldsId) doesn't get stamped with the new ID created thus I have no link between the 2 tables.

If I create a new OrderLine (not an existing row), everything is inserting correctly.

public class OrderLine
{
        public int OrderLineId { get; set; }
        public virtual OrderLineCustomFields OrderLineCustomFields { get; set; }
}

public class OrderLineCustomFields
{
    [DatabaseGenerated(DatabaseGeneratedOption.Identity)]
    [Key]
    public int OrderLineCustomFieldsId { get; set; }
    public string SomeValue { get; set; }
}

Sample New object:

var ol = new OrderLine();
ol.OrderLineId = 1;
ol.OrderLineCustomFields = new OrderLineCustomFields();
ol.OrderLineCustomFields.SomeValue = "NewValue";

Repository code:

var olEntity = context.OrderLines?
                .Where(x => x.OrderLineId == ol.OrderLineId)
                .FirstOrDefault();


var olCustomEntity = context.OrderLineCustomFields?
                .Where(x => ol.OrderLineCustomFields.OrderLineCustomFieldsId == x.OrderLineCustomFieldsId)
                .FirstOrDefault();

if (olCustomEntity == null)  //if there isn't a record already, then add it.
{
    context.Entry(ol.OrderLineCustomFields).State = EntityState.Added;
}
else  //else, update the record with new data
{
    ol.OrderLineCustomFields.OrderLineCustomFieldsId = olCustomEntity.OrderLineCustomFieldsId;
    context.Entry(olCustomEntity).CurrentValues.SetValues(ol.OrderLineCustomFields);
}

//Save the orderLine
context.Entry(olEntity).CurrentValues.SetValues(ol);
context.SaveChanges();

Answer 1

I was able to get it working. I didn't let EF know that the OrderLine was modified:

context.Entry(olEntity).State = EntityState.Modified;