Error condition is:
The driver tries to (de)serialize a mutlipolygon when it should be a polygon...

(note: point code works fine)

class in question has a property that is a polygon.

The data in the db has the loc field ... as a polygon ...the exception is listed below...

Offending class (identical to class using point)

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using MongoDB.Bson;
using MongoDB.Bson.Serialization.Attributes;
using MongoDB.Bson.Serialization.IdGenerators;
using MongoDB.Driver.GeoJsonObjectModel;

namespace WebApplicationFacebook.Helpers.Models
{
public class State
{
[BsonId(IdGenerator = typeof(ObjectIdGenerator))]
public ObjectId Id

{ get; set; }

[BsonElement("name")]
public string Name { get; set; }

[BsonElement("code")]
public string Code

{ get; set; }

[BsonElement("loc")]
public GeoJsonPolygon<GeoJson2DGeographicCoordinates> Loc { get; set; }

}
}

offending data .....

{
"_id" : ObjectId("536b0a143004b15885c91a20"),
"name" : "Wyoming",
"code" : "WY",
"loc" :

{ "type" : "Polygon", "coordinates" : [ [ [ -108.6213129999998700, 45.0002769999999830 ], [ -104.0576969999999500, 44.9973800000001350 ], [ -104.0532489999999900, 41.0014060000000880 ], [ -111.0467229999999900, 40.9979589999999800 ], [ -111.0551989999998900, 45.0013210000000750 ], [ -108.6213129999998700, 45.0002769999999830 ] ] ] }

}

{"An error occurred while deserializing the Loc property of class WebApplicationFacebook.Helpers.Models.State: Invalid GeoJson type: 'MultiPolygon'. Expected: 'Polygon'."}

System.AggregateException was unhandled by user code
HResult=-2146233088
Message=One or more errors occurred.
Source=mscorlib
StackTrace:
at System.Threading.Tasks.Task.ThrowIfExceptional(Boolean includeTaskCanceledExceptions)
at System.Threading.Tasks.Task`1.GetResultCore(Boolean waitCompletionNotification)
at System.Threading.Tasks.Task`1.get_Result()
at WebApplicationFacebook.Services.MongoGeoJsonRepository.GetStates() in c:\Git\WebApplicationFacebook\WebApplicationFacebook\Services\MongoGeoJsonRepository.cs:line 747
at ServiceTest.MongoRepositoryTests.TestMethodStates() in c:\Git\WebApplicationFacebook\ServiceTest\MongoRepositoryTests.cs:line 147
InnerException: System.FormatException
HResult=-2146233033
Message=An error occurred while deserializing the Loc property of class WebApplicationFacebook.Helpers.Models.State: Invalid GeoJson type: 'MultiPolygon'. Expected: 'Polygon'.
Source=MongoDB.Bson
StackTrace:
at MongoDB.Bson.Serialization.BsonClassMapSerializer`1.DeserializeMemberValue(BsonDeserializationContext context, BsonMemberMap memberMap)
at MongoDB.Bson.Serialization.BsonClassMapSerializer`1.DeserializeClass(BsonDeserializationContext context)
at MongoDB.Bson.Serialization.BsonClassMapSerializer`1.Deserialize(BsonDeserializationContext context, BsonDeserializationArgs args)
at MongoDB.Bson.Serialization.IBsonSerializerExtensions.Deserialize[TValue](IBsonSerializer`1 serializer, BsonDeserializationContext context)
at MongoDB.Driver.Core.WireProtocol.Messages.Encoders.BinaryEncoders.ReplyMessageBinaryEncoder`1.ReadMessage()
at MongoDB.Driver.Core.WireProtocol.Messages.Encoders.BinaryEncoders.ReplyMessageBinaryEncoder`1.MongoDB.Driver.Core.WireProtocol.Messages.Encoders.IMessageEncoder.ReadMessage()
at MongoDB.Driver.Core.Connections.BinaryConnection.<ReceiveMessageAsync>d__15.MoveNext()
— End of stack trace from previous location where exception was thrown —
at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
at System.Runtime.CompilerServices.ConfiguredTaskAwaitable`1.ConfiguredTaskAwaiter.GetResult()
at MongoDB.Driver.Core.WireProtocol.QueryWireProtocol`1.<ExecuteAsync>d__0.MoveNext()
— End of stack trace from previous location where exception was thrown —
at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
at System.Runtime.CompilerServices.ConfiguredTaskAwaitable`1.ConfiguredTaskAwaiter.GetResult()
at MongoDB.Driver.Core.Servers.ClusterableServer.ServerChannel.<ExecuteProtocolAsync>d__24`1.MoveNext()
— End of stack trace from previous location where exception was thrown —
at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
at System.Runtime.CompilerServices.ConfiguredTaskAwaitable`1.ConfiguredTaskAwaiter.GetResult()
at MongoDB.Driver.Core.Operations.FindOperation`1.<ExecuteAsync>d__2.MoveNext()
— End of stack trace from previous location where exception was thrown —
at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
at System.Runtime.CompilerServices.ConfiguredTaskAwaitable`1.ConfiguredTaskAwaiter.GetResult()
at MongoDB.Driver.OperationExecutor.<ExecuteReadOperationAsync>d__0`1.MoveNext()
— End of stack trace from previous location where exception was thrown —
at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
at System.Runtime.CompilerServices.ConfiguredTaskAwaitable`1.ConfiguredTaskAwaiter.GetResult()
at MongoDB.Driver.MongoCollectionImpl`1.<ExecuteReadOperation>d__35`1.MoveNext()
— End of stack trace from previous location where exception was thrown —
at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
at System.Runtime.CompilerServices.TaskAwaiter`1.GetResult()
at WebApplicationFacebook.Services.MongoGeoJsonRepository.<GetAllStates>d__75.MoveNext() in c:\Git\WebApplicationFacebook\WebApplicationFacebook\Services\MongoGeoJsonRepository.cs:line 755
InnerException: System.FormatException
HResult=-2146233033
Message=Invalid GeoJson type: 'MultiPolygon'. Expected: 'Polygon'.
Source=MongoDB.Driver
StackTrace:
at MongoDB.Driver.GeoJsonObjectModel.Serializers.GeoJsonObjectSerializerHelper`1.EnsureTypeIsValid(BsonDeserializationContext context)
at MongoDB.Driver.GeoJsonObjectModel.Serializers.GeoJsonObjectSerializerHelper`1.DeserializeBaseMember(BsonDeserializationContext context, String elementName, Int64 flag, GeoJsonObjectArgs`1 args)
at MongoDB.Driver.GeoJsonObjectModel.Serializers.GeoJsonPolygonSerializer`1.<>c_DisplayClass1.<DeserializeValue>b_0(String elementName, Int64 flag)
at MongoDB.Bson.Serialization.Serializers.SerializerHelper.DeserializeMembers(BsonDeserializationContext context, Action`2 memberHandler)
at MongoDB.Driver.GeoJsonObjectModel.Serializers.GeoJsonPolygonSerializer`1.DeserializeValue(BsonDeserializationContext context, BsonDeserializationArgs args)
at MongoDB.Bson.Serialization.Serializers.ClassSerializerBase`1.Deserialize(BsonDeserializationContext context, BsonDeserializationArgs args)
at MongoDB.Bson.Serialization.Serializers.SerializerBase`1.MongoDB.Bson.Serialization.IBsonSerializer.Deserialize(BsonDeserializationContext context, BsonDeserializationArgs args)
at MongoDB.Bson.Serialization.IBsonSerializerExtensions.Deserialize(IBsonSerializer serializer, BsonDeserializationContext context)
at MongoDB.Bson.Serialization.BsonClassMapSerializer`1.DeserializeMemberValue(BsonDeserializationContext context, BsonMemberMap memberMap)
InnerException:

.... test code is as follows:

public IMongoDatabase GetDataBase()
{
if (!localMongo.IsNullOrWhiteSpace())
{
if (!geoTest.IsNullOrWhiteSpace())
{
try
{
if (mongoClient == null)

{ mongoClient = new MongoClient(localMongo); }

return mongoClient.GetDatabase(geoTest);

}
catch (Exception exp)

{ log.Error("getDataBase failed", exp); }

}
}
throw new ApplicationException("Unable to create Mongo Client database is null");
}

public IMongoCollection<State> GetStatesCollection()

{ var db = GetDataBase(); var collection = db.GetCollection<State>("states"); return collection; }

public async Task<List<State>> GetAllStates()
{
var stateCollection = GetStatesCollection();
List<State> states = new List<State>();
using (var cursor = await stateCollection.FindAsync(p => p.Name != ""))
{
while (await cursor.MoveNextAsync())
{
var batch = cursor.Current;
foreach (var state in batch)

{ states.Add(state); }

}
}
return states;
}

Reporter: George Celvi
E-mail: georgepcelvi@aol.com