实体框架无法保存生产环境中的更改

Question

I am writing a desktop application that works with EF and MySql. There is a mapping of each type created by the EF to a local type. When testing the wrapper methods using the unit testing framework supplied by Visual Studio, all the test run -and I see the information going in and out of the database. However, when I run the same code from a temp console program I added for integration tests, the EF throws the following exception:

System.NullReferenceException: Object reference not set to an instance of an object.
   at MySql.Data.MySqlClient.MySqlClientFactory.get_MySqlDbProviderServicesInstance()
   at MySql.Data.MySqlClient.MySqlClientFactory.System.IServiceProvider.GetService(Type serviceType)
   at System.Data.Common.DbProviderServices.GetProviderServices(DbProviderFactory factory)
   at System.Data.Metadata.Edm.StoreItemCollection.Loader.InitializeProviderManifest(Action`3 addError)
   at System.Data.Metadata.Edm.StoreItemCollection.Loader.OnProviderManifestTokenNotification(String token, Action`3 addError)
   at System.Data.EntityModel.SchemaObjectModel.Schema.HandleProviderManifestTokenAttribute(XmlReader reader)
   at System.Data.EntityModel.SchemaObjectModel.Schema.HandleAttribute(XmlReader reader)
   at System.Data.EntityModel.SchemaObjectModel.SchemaElement.ParseAttribute(XmlReader reader)
   at System.Data.EntityModel.SchemaObjectModel.SchemaElement.Parse(XmlReader reader)
   at System.Data.EntityModel.SchemaObjectModel.Schema.HandleTopLevelSchemaElement(XmlReader reader)
   at System.Data.EntityModel.SchemaObjectModel.Schema.InternalParse(XmlReader sourceReader, String sourceLocation)
   at System.Data.EntityModel.SchemaObjectModel.Schema.Parse(XmlReader sourceReader, String sourceLocation)
   at System.Data.EntityModel.SchemaObjectModel.SchemaManager.ParseAndValidate(IEnumerable`1 xmlReaders, IEnumerable`1 sourceFilePaths, SchemaDataModelOption dataModel, AttributeValueNotification providerNotification, AttributeValueNotification providerManifestTokenNotification, ProviderManifestNeed
ed providerManifestNeeded, IList`1& schemaCollection)
   at System.Data.Metadata.Edm.StoreItemCollection.Loader.LoadItems(IEnumerable`1 xmlReaders, IEnumerable`1 sourceFilePaths)
   at System.Data.Metadata.Edm.StoreItemCollection.Init(IEnumerable`1 xmlReaders, IEnumerable`1 filePaths, Boolean throwOnError, DbProviderManifest& providerManifest, DbProviderFactory& providerFactory, String& providerManifestToken, Memoizer`2& cachedCTypeFunction)
   at System.Data.Metadata.Edm.StoreItemCollection..ctor(IEnumerable`1 xmlReaders, IEnumerable`1 filePaths)
   at System.Data.Metadata.Edm.MetadataCache.StoreMetadataEntry.LoadStoreCollection(EdmItemCollection edmItemCollection, MetadataArtifactLoader loader)
   at System.Data.Metadata.Edm.MetadataCache.StoreItemCollectionLoader.LoadItemCollection(StoreMetadataEntry entry)
   at System.Data.Metadata.Edm.MetadataCache.LoadItemCollection[T](IItemCollectionLoader`1 itemCollectionLoader, T entry)
   at System.Data.Metadata.Edm.MetadataCache.GetOrCreateStoreAndMappingItemCollections(String cacheKey, MetadataArtifactLoader loader, EdmItemCollection edmItemCollection, Object& entryToken)
   at System.Data.EntityClient.EntityConnection.LoadStoreItemCollections(MetadataWorkspace workspace, DbConnection storeConnection, DbProviderFactory factory, DbConnectionOptions connectionOptions, EdmItemCollection edmItemCollection, MetadataArtifactLoader artifactLoader)
   at System.Data.EntityClient.EntityConnection.GetMetadataWorkspace(Boolean initializeAllCollections)
   at System.Data.EntityClient.EntityConnection.InitializeMetadata(DbConnection newConnection, DbConnection originalConnection, Boolean closeOriginalConnectionOnFailure)
   at System.Data.EntityClient.EntityConnection.Open()
   at System.Data.Objects.ObjectContext.EnsureConnection()
   at System.Data.Objects.ObjectContext.SaveChanges(SaveOptions options)
   at System.Data.Objects.ObjectContext.SaveChanges()
   at DataAccess.PhoneTypeAccess.AddNewPhoneType(PhoneType newPhoneType) in C:\Users\Mordechai\Desktop\Progaming\GitHub\VirtualGabbai\VirtGabbai\DataAccess\PhoneTypeAccess.cs:line 66
   at TempUI.Program.Main(String[] args) in C:\Users\Mordechai\Desktop\Progaming\GitHub\VirtualGabbai\VirtGabbai\TempUI\Program.cs:line 17

Here is the code i run in program.cs

static void Main(string[] args)
        {
            try
            {
                PhoneTypeAccess.AddNewPhoneType(new PhoneType(1, "phone"));
                var blah = PhoneTypeAccess.GetPhoneTypeById(1);
                Console.WriteLine(blah.ToString());
                //Cache.CacheData.t_phone_types.AddObject(t_phone_types.Createt_phone_types(1, "some Type"));
                //var thingOne = t_people.Createt_people(1);
                //Cache.CacheData.t_people.AddObject(thingOne);
                //Cache.CacheData.SaveChanges();
                //PhoneNumberAccess.AddNewPhoneNumber(new PhoneNumber(1, "some number", new PhoneType(1, "some type")));
                //var test = PhoneNumberAccess.GetPhoneNumberById(1);
                //Console.WriteLine(test.ToString
            }
            catch (Exception e)
            {
                Console.WriteLine(e.ToString());
            }
        }

The test contains the following code

[TestMethod()]
    public void AddNewPhoneTypeTest()
    {
        PhoneType newPhoneType = new PhoneType(21, "phonetype:21");
        PhoneTypeAccess.AddNewPhoneType(newPhoneType);
        PhoneType actual = PhoneTypeAccess.GetPhoneTypeById(21);
        Assert.IsTrue(newPhoneType.Equals(actual));
    }

And the code being called is as follows

 public static void AddNewPhoneType(PhoneType newPhoneType)
    {
        t_phone_types phoneTypeToAdd = PhoneTypeAccess.ConvertSingleLocalPhoneTypeToDbType(newPhoneType);
        Cache.CacheData.t_phone_types.AddObject(phoneTypeToAdd);
        Cache.CacheData.SaveChanges();
    }

When i went in with debug at the line Cache.CacheData.SaveChanges() , I get to the following code

/// <summary>
/// Allows access to the cached data - but only a single (and constant) instance of it
///  -[the code can create another one but it will be a completly different set of data]-
/// </summary>
public static class Cache
{
    // Data members
    private static zera_leviEntities m_dsDataSet = new zera_leviEntities();

    /// <summary>
    /// Allows outside access to the main data set
    ///  - without letting the user access it any other way
    /// </summary>
    public static zera_leviEntities CacheData
    {
        get
        {
            return m_dsDataSet;
        }
    }
}

and the only thing I could see was the fact that in the entity set there really was no object. but there was no indication as to why I've looked all over and didnt find anything that helped. I am stuck until I get this running so I hope someone can help me Thank you

Edit: Added in the conversion method

private static t_phone_types ConvertSingleLocalPhoneTypeToDbType(PhoneType localTypePhoneType)
    {
        return t_phone_types.Createt_phone_types(localTypePhoneType._Id, localTypePhoneType.PhoneTypeName);
    }

The t_phone_types.Createt_phone_types() method is part of the EF

Edit: I've managed to break the tests also now by changing the references in the whole solution to an updated version of the MySql Adapter Now the tests also throw the same exception. In addition when building I get the following error:

Error 4: Could not load file or assembly 'MySql.Data, Version=6.7.4.0, Culture=neutral, PublicKeyToken=c5687fc88969c44d' or one of its dependencies. The located assembly's manifest definition does not match the assembly reference. (Exception from HRESULT: 0x80131040) C:\Users\Mordechai\Desktop\Progaming\GitHub\VirtualGabbai\VirtGabbai\Data\EntityCache.edmx

BUT, it will still run (just that it throws the exception)

Answer 1

Well...., I managed to figure out the problem after much trial and error. The MySQl adapter comes in 2 parts. One for all connections and an additional piece for connecting specifically with EF. Now that I added the second dll it all runs fine.