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I'm trying to serialize a C# object to a JSON object. Here's the code:

QuestionGroup group = DatabaseMethods.GetQuestionGroup(questionGroupID);
JavaScriptSerializer jSer = new JavaScriptSerializer();
string json = jSer.Serialize(group);

group looks as expected after line 1. The third line never returns anything, and I can't step into the function; I can only look at metadata and it doesn't mention anything about this. I'm not getting an exception; it just...never...returns.

The object I'm passing it is a pretty beastly class that has children and grandchildren. It's an EF class; I don't know if that could somehow be messing with the JSON serializer. It's supposed to take any object so I don't see how that would; but who knows.

Here's the class, with some code removed for conciseness:

public class QuestionGroup
{
    public Int32 QuestionGroupID { get; set; }
    public Int32 Order { get; set; }

    [Display(Name = "Path to File", Prompt = "Path to File")]
    [DataType(DataType.Upload)]

    [NotMapped]
    public HttpPostedFileWrapper PathToFile { get; set; }
    public String FileName { get; set; }
    public virtual Image Image { get; set; }
    public Int32? ImageID {get; set; }

    public String Text { get; set; }
    public DateTime WhenCreated { get; set; }
    public Int32 CreatedBy { get; set; }

    [NotMapped]
    public Int32 MasteryCriteriaNumerator { get; set; }
    [NotMapped]
    public Int32 MasteryCriteriaDenominator { get; set; }

    public Boolean TeacherAdministersToStudent { get; set; }

    /*Foreign keys for associations*************************************************/
    public Guid MasteryObjectiveID { get; set; }

    /*Navigational properties for EF************************************************/
    public MasteryObjective MasteryObjective {
        get { return DAL.DatabaseMethods.GetMasteryObjective(MasteryObjectiveID); }
    }
    public List<Question> Questions{ get; set; }
    public virtual List<Assessment> Assessments { get; set; }
    public virtual List<MultipleChoiceResult> MultipleChoiceResults { get; set; }

    // The full url to qg's image on rackspace
    [NotMapped]
    public String RackspaceFullURL { get { return GetRackspaceURL(QuestionGroupID, FileName); } }

    private String GetRackspaceURL(Int32 QuestionGroup, String FileName)
    {
        //code removed
    }
}
levininja
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    You may be experiencing a `StackOverflowException`. However, `JavaScriptSerializer` detects circular references and throws an exception when one is encountered, so the most likely cause of such an exception doesn't apply here. Try adding [`[ScriptIgnore]`](https://msdn.microsoft.com/en-us/library/system.web.script.serialization.scriptignoreattribute%28v=vs.110%29.aspx) to successive properties to try to narrow down the problem. – dbc Mar 23 '15 at 19:16
  • @dbc I put `[ScriptIgnore]` on a property I've been suspecting, and got different results. Now it throws an `{"The ObjectContext instance has been disposed and can no longer be used for operations that require a connection."}`. – levininja Mar 23 '15 at 19:26
  • Try disabling lazy loading of properties, as is discussed here: https://stackoverflow.com/questions/18398356/how-to-solve-the-error-the-objectcontext-instance-has-been-disposed-and-can-no-l – dbc Mar 23 '15 at 19:33
  • @dbc some of the properties need to be lazy-loaded because certain operations get way too slow otherwise... :-( – levininja Mar 23 '15 at 19:41
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    Could you serialize to JSON before disposing of your DbContext? – dbc Mar 23 '15 at 19:46
  • More suggestions here: https://stackoverflow.com/questions/4206634/system-objectdisposedexception-the-objectcontext-instance-has-been-disposed-and – dbc Mar 23 '15 at 19:49
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    Hm...so I tried serializing the JSON in the actual database method so it was done before DbContext was dispose of...but that has revealed that the problem isn't with the property I thought. Actually, I applied that attribute to almost every property and I've still got the same problem (it just doesn't ever return anything). So at this point...I've spent too much time on this, so I'm just going to hardcode a method for mapping the object to a JSON object manually. :-( – levininja Mar 23 '15 at 20:17

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