DbDataController in MVC4 UpdateEntity failing

Question

I have a datamodel like

ModelA which contains a Collection.

ModelB contains a Collection as a backreference. That is failing because of cyclic references if I query with Include("ModelB"). Not good but I solved that via setting ModelB.List=null for each element.

The problem now is submitting a changed ModelA tree: I am adding ModelB-entities to ModelA.ModelB[]. Now the UpdateEntity function is complaining the it could not add elements of type ModelB which are declared static. The JSON deserializer is creating static arrays.

How is it possible with the combination of upshot/MVC4 to submit datamodels which are not completely flat? As it is not possible right now to create your own DTO objects where you might figure out something I am stuck now...

After investigating the error a bit better, I think the problem is the cyclic backreference:

The ModelA->ModelB->ModelA is breaking the storage of the data. "Could not add data of type ModelA to type ModelB". As I mentioned the backreference was set to Null because the cyclic ref serialisation problem...

I hope the will be some easier way on doing more manually with DTO objects where I have mroe control.

Please see also: MVC 4, Upshot entities cyclic references for the beginning of the journey...

score 1 · Answer 1 · edited May 23 '17 at 10:28

To solve the cyclic backreference, you can use the ignoreDataMember attribute:

public class Customer
{
    [Key]
    public int CustomerId { get; set; }

    public string Name { get; set; }
    public string Address { get; set; }
    public double Latitude { get; set; }
    public double Longitude { get; set; }

    public virtual ICollection<Delivery> Deliveries { get; set; }
}

public class Delivery
{
    [Key]
    public int DeliveryId { get; set; }
    public string Description { get; set; }
    public bool IsDelivered { get; set; }

    [IgnoreDataMember]
    public virtual Customer Customer { get; set; }
    public virtual int CustomerId { get; set; }
}

I posted a working solution to your problem in a different question: https://stackoverflow.com/a/10010695/1226140

DbDataController in MVC4 UpdateEntity failing

1 Answers1