Сериализация проблем Entity Framework

Я решил эти проблемы с помощью следующих классов:

public class EFJavaScriptSerializer : JavaScriptSerializer
  {
    public EFJavaScriptSerializer()
    {
      RegisterConverters(new List<JavaScriptConverter>{new EFJavaScriptConverter()});
    }
  }

а также

public class EFJavaScriptConverter : JavaScriptConverter
  {
    private int _currentDepth = 1;
    private readonly int _maxDepth = 1;

    private readonly List<object> _processedObjects = new List<object>();

    private readonly Type[] _builtInTypes = new[]
    {
      typeof(int?),
      typeof(double?),
      typeof(bool?),
      typeof(bool),
      typeof(byte),
      typeof(sbyte),
      typeof(char),
      typeof(decimal),
      typeof(double),
      typeof(float),
      typeof(int),
      typeof(uint),
      typeof(long),
      typeof(ulong),
      typeof(short),
      typeof(ushort),
      typeof(string),
      typeof(DateTime),
      typeof(DateTime?),
      typeof(Guid)
  };
    public EFJavaScriptConverter() : this(1, null) { }

    public EFJavaScriptConverter(int maxDepth = 1, EFJavaScriptConverter parent = null)
    {
      _maxDepth = maxDepth;
      if (parent != null)
      {
        _currentDepth += parent._currentDepth;
      }
    }

    public override object Deserialize(IDictionary<string, object> dictionary, Type type, JavaScriptSerializer serializer)
    {
      return null;
    }

    public override IDictionary<string, object> Serialize(object obj, JavaScriptSerializer serializer)
    {
      _processedObjects.Add(obj.GetHashCode());
      var type = obj.GetType();

      var properties = from p in type.GetProperties()
                       where p.CanRead && p.GetIndexParameters().Count() == 0 &&
                             _builtInTypes.Contains(p.PropertyType)
                       select p;

      var result = properties.ToDictionary(
                    p => p.Name,
                    p => (Object)TryGetStringValue(p, obj));

      if (_maxDepth >= _currentDepth)
      {
        var complexProperties = from p in type.GetProperties()
                                where p.CanRead &&
                                      p.GetIndexParameters().Count() == 0 &&
                                      !_builtInTypes.Contains(p.PropertyType) &&
                                      p.Name != "RelationshipManager" &&
                                      !AllreadyAdded(p, obj)
                                select p;

        foreach (var property in complexProperties)
        {
          var complexValue = TryGetValue(property, obj);

          if(complexValue != null)
          {
            var js = new EFJavaScriptConverter(_maxDepth - _currentDepth, this);

            result.Add(property.Name, js.Serialize(complexValue, new EFJavaScriptSerializer()));
          }
        }
      }

      return result;
    }

    private bool AllreadyAdded(PropertyInfo p, object obj)
    {
      var val = TryGetValue(p, obj);
      return _processedObjects.Contains(val == null ? 0 : val.GetHashCode());
    }

    private static object TryGetValue(PropertyInfo p, object obj)
    {
      var parameters = p.GetIndexParameters();
      if (parameters.Length == 0)
      {
        return p.GetValue(obj, null);
      }
      else
      {
        //cant serialize these
        return null;
      }
    }

    private static object TryGetStringValue(PropertyInfo p, object obj)
    {
      if (p.GetIndexParameters().Length == 0)
      {
        var val = p.GetValue(obj, null);
        return val;
      }
      else
      {
        return string.Empty;
      }
    }

    public override IEnumerable<Type> SupportedTypes
    {
      get
      {
        var types = new List<Type>();

        //ef types
        types.AddRange(Assembly.GetAssembly(typeof(DbContext)).GetTypes());
        //model types
        types.AddRange(Assembly.GetAssembly(typeof(BaseViewModel)).GetTypes());


        return types;

      }
    }
  }

Теперь вы можете безопасно звонить, как new EFJavaScriptSerializer().Serialize(obj)

Обновление : начиная с версии Telerik v1.3 + вы можете теперь переопределить метод GridActionAttribute.CreateActionResult и, следовательно, вы можете легко интегрировать этот сериализатор в определенные методы контроллера, применяя свой собственный [GridAction] :

[Grid]
public ActionResult _GetOrders(int id)
{ 
   return new GridModel(Service.GetOrders(id));
}

а также

public class GridAttribute : GridActionAttribute, IActionFilter
  {    
    /// <summary>
    /// Determines the depth that the serializer will traverse
    /// </summary>
    public int SerializationDepth { get; set; } 

    /// <summary>
    /// Initializes a new instance of the <see cref="GridActionAttribute"/> class.
    /// </summary>
    public GridAttribute()
      : base()
    {
      ActionParameterName = "command";
      SerializationDepth = 1;
    }

    protected override ActionResult CreateActionResult(object model)
    {    
      return new EFJsonResult
      {
       Data = model,
       JsonRequestBehavior = JsonRequestBehavior.AllowGet,
       MaxSerializationDepth = SerializationDepth
      };
    }
}

и наконец..

public class EFJsonResult : JsonResult
  {
    const string JsonRequest_GetNotAllowed = "This request has been blocked because sensitive information could be disclosed to third party web sites when this is used in a GET request. To allow GET requests, set JsonRequestBehavior to AllowGet.";

    public EFJsonResult()
    {
      MaxJsonLength = 1024000000;
      RecursionLimit = 10;
      MaxSerializationDepth = 1;
    }

    public int MaxJsonLength { get; set; }
    public int RecursionLimit { get; set; }
    public int MaxSerializationDepth { get; set; }

    public override void ExecuteResult(ControllerContext context)
    {
      if (context == null)
      {
        throw new ArgumentNullException("context");
      }

      if (JsonRequestBehavior == JsonRequestBehavior.DenyGet &&
          String.Equals(context.HttpContext.Request.HttpMethod, "GET", StringComparison.OrdinalIgnoreCase))
      {
        throw new InvalidOperationException(JsonRequest_GetNotAllowed);
      }

      var response = context.HttpContext.Response;

      if (!String.IsNullOrEmpty(ContentType))
      {
        response.ContentType = ContentType;
      }
      else
      {
        response.ContentType = "application/json";
      }

      if (ContentEncoding != null)
      {
        response.ContentEncoding = ContentEncoding;
      }

      if (Data != null)
      {
        var serializer = new JavaScriptSerializer
        {
          MaxJsonLength = MaxJsonLength,
          RecursionLimit = RecursionLimit
        };

        serializer.RegisterConverters(new List<JavaScriptConverter> { new EFJsonConverter(MaxSerializationDepth) });

        response.Write(serializer.Serialize(Data));
      }
    }