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Handling Circular Reference in EF and DataSourceResult

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This is a migrated thread and some comments may be shown as answers.
Pierre
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Pierre asked on 18 Sep 2018, 08:19 PM

HI, I try to search and I can't found a way to handling the circular reference error caused when serialize DataSourceResult containing EF FK with Include.

For exemple my 2  EF class:

public class ActionGES
 {
     public int ActionGESID { get; set; }
     [Required]
     public int MunicipaliteId { get; set; }
     [MaxLength(250), Required]
     public string Titre { get; set; }
     [Required]
     public string Description { get; set; }
     [Required]
     public int AnneeDepart { get; set; }
     [Required]
     public int AnneeCible { get; set; }
     [Required]
     public int ObjectifCible { get; set; }
     [Required]
     public string UniteIndicateur { get; set; }
     public ICollection<IndicateurAction> Indicateurs { get; set; }
 
     public int SecteurId { get; set; }
     public Secteur Secteur { get; set; }
 
     public int Ordre { get; set; }
     public string FormuleGES { get; set; }
     public string ImageUrl { get; set; }
     public bool ApprouveEA { get; set; }
 
     [Required]
     public bool Archive { get; set; }
 
 
 }
 
 public class IndicateurAction
 {
     public int IndicateurActionID { get; set; }
     [Required]
     public int Indicateur { get; set; }
     [Required]
     public int Annee { get; set; }
     public bool ApprouveEA { get; set; }
 
     //FK Key
     public int ActionGESId { get; set; }
     public ActionGES ActionGES { get; set; }
 }

The EF line for the Get (called be the controller)

var ctx = new PortailGESContext();
Actions = ctx.Actions.Where(a => a.Archive == false & a.MunicipaliteId == MunicipaliteId).OrderBy(o => o.Ordre).Include(s=>s.Secteur).Include(s => s.Indicateurs);

Then the controller action:

//GET: ActionSommaire_Read
[Authorize]
public async Task<ActionResult> Actions_ReadAsync([DataSourceRequest]DataSourceRequest request)
{
    IQueryable<ActionGES> actions;
 
    if (Session["MunicipaliteIdSel"] != null && Convert.ToInt32(Session["MunicipaliteIdSel"]) > 0)
    {
        actions = this.actionService.GetActionsActive(Convert.ToInt32(Session["MunicipaliteIdSel"]));
    }
    else
    {
        actions = Enumerable.Empty<ActionGES>().AsQueryable();
        ModelState.AddModelError("Error: no ID...", "");
    }
     
    DataSourceResult dsResult = await actions.ToDataSourceResultAsync(request, ModelState);
 
 
 
    return Json(dsResult, JsonRequestBehavior.AllowGet);           
}

 

This give me a circular reference when serializing Json. After reading on the web, I try to add this line to convert myself in JSON before returning it to the view:

var result = JsonConvert.SerializeObject(dsResult, Formatting.None,
                           new JsonSerializerSettings
                           {
                               ReferenceLoopHandling = ReferenceLoopHandling.Ignore
                           });

This time the convertrion work well with out circular reference, but the Json receive by the view is not the same. So the grid do not work.

Result with Json(result):  {"Data":[{"ActionGESID":1,"MunicipaliteId":1,"Titre":"test" ......
Result with JsonConvert.SerializeObject:  "{\"Data\":[{\"ActionGESID\":1,\"MunicipaliteId\":1,\"Titre\":\"Test\" .....

Any idea to handle this?

Thanks

 

 

2 Answers, 1 is accepted

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Angel Petrov
Telerik team
answered on 20 Sep 2018, 10:22 AM
Hello,

This is a commonly encountered problem. One thing you can do is disable proxy creation as  suggested here. Another thing that you can try use a third party library for serialization and manually create an object of type DataSourceResult and assign the data to its Data property.

Regards,
Angel Petrov
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Pierre
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answered on 20 Sep 2018, 03:14 PM

Thanks for reply. But for now I just use the annotation [ScriptIgnore] on the navigation propertie of the child object and that work.

[ScriptIgnore]
public ActionGES ActionGES { get; set; }
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Angel Petrov
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Pierre
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