Bug 14026 - System.InvalidCastException at (wrapper unknown) object:gsharedvt_in ()
Summary: System.InvalidCastException at (wrapper unknown) object:gsharedvt_in ()
Alias: None
Product: iOS
Classification: Xamarin
Component: XI runtime ()
Version: 6.4.0
Hardware: Other Mac OS
: --- normal
Target Milestone: Untriaged
Assignee: Zoltan Varga
Depends on:
Reported: 2013-08-16 06:01 UTC by artur.drobinskiy
Modified: 2013-08-20 10:11 UTC (History)
3 users (show)

Is this bug a regression?: ---
Last known good build:

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Description artur.drobinskiy 2013-08-16 06:01:20 UTC
Initially posted in forums (http://forums.xamarin.com/discussion/7103/system-invalidcastexception-at-wrapper-unknown-object-gsharedvt-in?new=1), it was suggested to file a bug here.

With the latest beta (Xamarin.iOS 6.4.3) I got the exception when deserializing xml received from web service
(especially, when deserializing Dictionary<Enum, int>)

System.AggregateException: ---> System.InvalidCastException: Cannot cast from source type to destination type. at (wrapper managed-to-native) object:__icall_wrapper_mono_object_castclass_unbox (object,intptr) at System.Collections.Generic.Dictionary2[CompanyName.Enumerations.Pub.ImageSize,System.Int32].ToTKey (System.Object key) [0x00000] in <filename unknown>:0 
  at (wrapper unknown) object:gsharedvt_in ()
  at (wrapper unknown) object:gsharedvt_out ()
  at System.Collections.Generic.Dictionary
2[CompanyName.Enumerations.Pub.ImageSize,System.Int32].System.Collections.IDictionary.Add (System.Object key, System.Object value) [0x00000] in :0 at System.Runtime.Serialization.DictionaryTypeMap.DeserializeContent (System.Xml.XmlReader reader, System.Runtime.Serialization.XmlFormatterDeserializer deserializer, System.String id) [0x00000] in :0 at System.Runtime.Serialization.SerializationMap.DeserializeObject (System.Xml.XmlReader reader, System.Runtime.Serialization.XmlFormatterDeserializer deserializer) [0x00000] in :0 at System.Runtime.Serialization.XmlFormatterDeserializer.DeserializeByMap (System.Xml.XmlQualifiedName name, System.Type type, System.Xml.XmlReader reader) [0x00000] in :0 at System.Runtime.Serialization.XmlFormatterDeserializer.Deserialize (System.Type type, System.Xml.XmlReader reader) [0x00000] in :0 at System.Runtime.Serialization.SerializationMap.DeserializeContent (System.Xml.XmlReader reader, System.Runtime.Serialization.XmlFormatterDeserializer deserializer, System.String id, Boolean empty) [0x00000] in :0

The code worked with Xamarin.Ios Stable (6.4.1)

Here's the failing test:
        public void ImagesSerialization()
            var instance = new ImagesSerializationTestDTO();
            instance.Images = new Dictionary<EnumTest, int>();
            instance.Images.Add(EnumTest.One, 10);

            MemoryStream stream = new MemoryStream();
            DataContractSerializer serializer = new DataContractSerializer(typeof(ImagesSerializationTestDTO));
            serializer.WriteObject(stream, instance);

            stream.Position = 0;
            string serializedText = new StreamReader(stream).ReadToEnd();
            stream.Position = 0;
            ImagesSerializationTestDTO deserialized = serializer.ReadObject(stream) as ImagesSerializationTestDTO;

            Assert.AreEqual(1, deserialized.Images.Count);


    public enum EnumTest : int
        One = 1,
        Two = 2,
    [DataContract(Namespace = "ServiceLibraryTests")]
    public class ImagesSerializationTestDTO
        public Dictionary<EnumTest, int> Images
Comment 1 Zoltan Varga 2013-08-20 10:11:41 UTC
Fixed in master/mono-3-2. Backported to monotouch-6.4-series.