从 SQL 连接创建实体连接时出现问题

Question

We are converting our DB access to use Azure Identity with EF. I tried various different methods and failed because EF is expecting a model to be created and passed into the connection string which i was unable to do with DBConnection. Finally I found a way to create the EntityConnection from a SQLConnection so I can retain all the information from the original connection string and add the metadata as needed. Here's my code:

public static EntityConnection GetEntityConnectionString( string efConnectionString, string accessToken )
        {
            MetadataWorkspace workspace = new MetadataWorkspace( new string[] { "res://*/" }, new Assembly[] { Assembly.GetExecutingAssembly() } );
                        
            SqlConnection sqlConnection = new SqlConnection( efConnectionString );
            sqlConnection.AccessToken = accessToken;
            EntityConnection entityConnection = new EntityConnection( workspace, sqlConnection );
            return entityConnection;
        }

When I run this and get to the

EntityConnection entityConnection = new EntityConnection( workspace, sqlConnection );

I get the following error:

System.ArgumentException: 'MetadataWorkspace must have EdmItemCollection pre-registered.'

Not sure what to do at this point and would really appreciate any insight that can be provided.

Answer 1

In case anyone else runs into this, here's what I had to do to resolve the issue

public static EntityConnection GetEntityConnectionString( string efConnectionString, string accessToken )
        {

            MetadataWorkspace workspace = new MetadataWorkspace( new string[] { metadata[0] }, new Assembly[] { Assembly.GetExecutingAssembly() } );

            var edmItemCollection = new EdmItemCollection( "res://*/<filename>.csdl" );
            var store = new StoreItemCollection( "res://*/<filename>.ssdl" );
            var mapping = new StorageMappingItemCollection( edmItemCollection, store, "res://*/<filename>.msl" );


            workspace.RegisterItemCollection( edmItemCollection );
            workspace.RegisterItemCollection( store );
            workspace.RegisterItemCollection( mapping );
            SqlConnection sqlConnection = new SqlConnection( efConnectionString );
            sqlConnection.AccessToken = accessToken;
            EntityConnection entityConnection = new EntityConnection( workspace, sqlConnection );
            return entityConnection;
        }

Answer 2

https://social.msdn.microsoft.com/Forums/en-US/dd7b1c41-e428-4e29-ab83-448d3f529ba4/creating-an-entity-connection-from-a-sql-connection?forum=adodotnetentityframework we can create a new EntityConnection from a MetaDataWorkspace that I then use to construct a DbContext with a different schema