Question

I’m trying to make a generic handler post a JSONJ object based on my entity type SYSTEM_AUDIT_SHEET:

SYSTEM_AUDIT_SHEET sheet = ctx.SYSTEM_AUDIT_SHEET
                              .Where(s => s.SYSTEM_KEY == system_key_dec)
                              .Select(s => s)
                              .OrderByDescending(s => s.AUDIT_SHEET_VERSION)
                              .First();

HttpContext.Current.Response.Write(serializer.Serialize(sheet));

But I get the following error:

A circular reference was detected while serializing an object of type
‘System.Data.Entity.DynamicProxies.SYSTEM_AUDIT_SHEET_521A7B786A51FC0F83641182DD72C8DFE6C082418D30BBB977B403409A74CE17’.

Why can’t I convert the entity to JSON?

Answer 1

You cannot convert objects to json that reference themselves as this would create an infinitely long json string.

For example, the following pseudo-code wouldn’t work because it sets up a circular reference (Dog >> Bone >> Dog…):

class Dog {
    private Bone myBone;
    public Dog() {
        myBone = new Bone(this);
    }
}

class Bone {
    private Dog buriedBy;
    public Bone(Dog d) {
        buriedBy = d;
    }
}

There seem to be some good solutions by googling ‘json circular reference’. See the top two stack overflow links.